diff --git a/espresso/data/__init__.py b/espresso/data/__init__.py
index 1522105693..8edd372e5c 100644
--- a/espresso/data/__init__.py
+++ b/espresso/data/__init__.py
@@ -6,6 +6,7 @@
 from .asr_bucket_pad_length_dataset import FeatBucketPadLengthDataset, TextBucketPadLengthDataset
 from .asr_chain_dataset import AsrChainDataset, NumeratorGraphDataset
 from .asr_dataset import AsrDataset
+from .asr_k2_dataset import AsrK2Dataset
 from .asr_dictionary import AsrDictionary
 from .asr_xent_dataset import AliScpCachedDataset, AsrXentDataset
 from .feat_text_dataset import (
@@ -20,6 +21,7 @@
     "AsrChainDataset",
     "AsrDataset",
     "AsrDictionary",
+    "AsrK2Dataset",
     "AsrTextDataset",
     "AsrXentDataset",
     "FeatBucketPadLengthDataset",
diff --git a/espresso/data/asr_k2_dataset.py b/espresso/data/asr_k2_dataset.py
new file mode 100644
index 0000000000..1735ea8eca
--- /dev/null
+++ b/espresso/data/asr_k2_dataset.py
@@ -0,0 +1,260 @@
+# Copyright (c) Yiming Wang, Yiwen Shao
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+import logging
+import os
+import re
+from typing import Dict, List
+
+import numpy as np
+
+import torch
+
+from fairseq.data import FairseqDataset, data_utils
+
+import espresso.tools.utils as speech_utils
+
+
+logger = logging.getLogger(__name__) 
+
+
+try:
+    from espresso.tools.lhotse.cut import CutSet
+except ImportError:
+    logger.warning("Please install Lhotse by `make lhotse` after entering espresso/tools")
+
+
+def collate(samples, pad_to_length=None, pad_to_multiple=1):
+    if len(samples) == 0:
+        return {}
+
+    def merge(key, pad_to_length=None):
+        if key == "source":
+            return speech_utils.collate_frames(
+                [sample[key] for sample in samples], 0.0,
+                pad_to_length=pad_to_length,
+                pad_to_multiple=pad_to_multiple,
+            )
+        else:
+            raise ValueError("Invalid key.")
+
+    id = torch.LongTensor([sample["id"] for sample in samples])
+    src_frames = merge(
+        "source",
+        pad_to_length=pad_to_length["source"] if pad_to_length is not None else None,
+    )
+    # sort by descending source length
+    if pad_to_length is not None:
+        src_lengths = torch.IntTensor(
+            [sample["source"].ne(0.0).any(dim=1).int().sum() for sample in samples]
+        )
+    else:
+        src_lengths = torch.IntTensor([s["source"].size(0) for s in samples])
+    src_lengths, sort_order = src_lengths.sort(descending=True)
+    id = id.index_select(0, sort_order)
+    utt_id = [samples[i]["utt_id"] for i in sort_order.numpy()]
+    src_frames = src_frames.index_select(0, sort_order)
+    ntokens = src_lengths.sum().item()
+
+    target = None
+    if samples[0].get("target", None) is not None and len(samples[0].target) > 0:
+        # reorder the list of samples to make things easier
+        # (no need to reorder every element in target)
+        samples = [samples[i] for i in sort_order.numpy()]
+
+        from torch.utils.data._utils.collate import default_collate
+
+        dataset_idx_to_batch_idx = {
+            sample["target"][0]["sequence_idx"]: batch_idx
+            for batch_idx, sample in enumerate(samples)
+        }
+
+        def update(d: Dict, **kwargs) -> Dict:
+            for key, value in kwargs.items():
+                d[key] = value
+            return d
+
+        target = default_collate([
+            update(sup, sequence_idx=dataset_idx_to_batch_idx[sup["sequence_idx"]])
+            for sample in samples
+            for sup in sample["target"]
+        ])
+
+    batch = {
+        "id": id,
+        "utt_id": utt_id,
+        "nsentences": len(samples),
+        "ntokens": ntokens,
+        "net_input": {
+            "src_tokens": src_frames,
+            "src_lengths": src_lengths,
+        },
+        "target": target,
+    }
+    return batch
+
+
+class AsrK2Dataset(FairseqDataset):
+    """
+    A K2 Dataset for ASR.
+
+    Args:
+        cuts (lhotse.CutSet): Lhotse CutSet to wrap
+        shuffle (bool, optional): shuffle dataset elements before batching
+            (default: True).
+        pad_to_multiple (int, optional): pad src lengths to a multiple of this value
+    """
+
+    def __init__(
+        self,
+        cuts: CutSet,
+        shuffle=True,
+        pad_to_multiple=1,
+    ):
+        self.cuts = cuts
+        self.cut_ids = list(self.cuts.ids)
+        self.src_sizes = np.array(
+            [cut.num_frames if cut.has_features else cut.num_samples for cut in cuts]
+        )
+        self.tgt_sizes = None
+        # assume all cuts have no supervisions if the first one does not
+        if len(cuts[self.cut_ids[0]].supervisions) > 0:
+            # take the size of the first supervision
+            self.tgt_sizes = np.array(
+                [
+                    round(
+                        cut.supervisions[0].trim(cut.duration).duration / cut.frame_shift
+                    ) for cut in cuts
+                ]
+            )
+        self.shuffle = shuffle
+        self.epoch = 1
+        self.sizes = (
+            np.vstack((self.src_sizes, self.tgt_sizes)).T
+            if self.tgt_sizes is not None
+            else self.src_sizes
+        )
+        self.pad_to_multiple = pad_to_multiple
+        self.feat_dim = self.cuts[self.cut_ids[0]].load_features().shape(1)
+
+    def __getitem__(self, index):
+        cut_id = self.cut_ids[index]
+        cut = self.cuts[cut_id]
+        features = torch.from_numpy(cut.load_features())
+
+        example = {
+            "id": index,
+            "utt_id": cut_id,
+            "source": features,
+            "target": [
+                {
+                    "sequence_idx": index,
+                    "text": sup.text,
+                    "start_frame": round(sup.start / cut.frame_shift),
+                    "num_frames": round(sup.duration / cut.frame_shift),
+                }
+                # CutSet's supervisions can exceed the cut, when the cut starts/ends in the middle
+                # of a supervision (they would have relative times e.g. -2 seconds start, meaning
+                # it started 2 seconds before the Cut starts). We use s.trim() to get rid of that
+                # property, ensuring the supervision time span does not exceed that of the cut.
+                for sup in (s.trim(cut.duration) for s in cut.supervisions)
+            ]
+        }
+        return example
+
+    def __len__(self):
+        return len(self.cuts)
+
+    def collater(self, samples, pad_to_length=None):
+        """Merge a list of samples to form a mini-batch.
+
+        Args:
+            samples (List[dict]): samples to collate
+            pad_to_length (dict, optional): a dictionary of
+                {"source": source_pad_to_length}
+                to indicate the max length to pad to in source and target respectively.
+
+        Returns:
+            dict: a mini-batch with the following keys:
+
+                - `id` (LongTensor): example IDs in the original input order
+                - `utt_id` (List[str]): list of utterance ids
+                - `nsentences` (int): batch size
+                - `ntokens` (int): total number of tokens in the batch
+                - `net_input` (dict): the input to the Model, containing keys:
+
+                  - `src_tokens` (FloatTensor): a padded 3D Tensor of features in
+                    the source of shape `(bsz, src_len, feat_dim)`.
+                  - `src_lengths` (IntTensor): 1D Tensor of the unpadded
+                    lengths of each source sequence of shape `(bsz)`
+
+                - `target` (List[Dict[str, Any]]): an List representing a batch of
+                    supervisions
+        """
+        return collate(
+            samples, pad_to_length=pad_to_length, pad_to_multiple=self.pad_to_multiple,
+        )
+
+    def num_tokens(self, index):
+        """Return the number of frames in a sample. This value is used to
+        enforce ``--max-tokens`` during batching."""
+        return self.src_sizes[index]
+
+    def size(self, index):
+        """Return an example's size as a float or tuple. This value is used when
+        filtering a dataset with ``--max-positions``."""
+        return (
+            self.src_sizes[index],
+            self.tgt_sizes[index] if self.tgt_sizes is not None else 0,
+        )
+
+    def ordered_indices(self):
+        """Return an ordered list of indices. Batches will be constructed based
+        on this order."""
+        if self.shuffle:
+            indices = np.random.permutation(len(self)).astype(np.int64)
+        else:
+            indices = np.arange(len(self), dtype=np.int64)
+        # sort by target length, then source length
+        if self.tgt_sizes is not None:
+            indices = indices[np.argsort(self.tgt_sizes[indices], kind="mergesort")]
+        return indices[np.argsort(self.src_sizes[indices], kind="mergesort")]
+
+    @property
+    def supports_prefetch(self):
+        return False
+
+    def filter_indices_by_size(self, indices, max_sizes):
+        """Filter a list of sample indices. Remove those that are longer
+            than specified in max_sizes.
+
+        Args:
+            indices (np.array): original array of sample indices
+            max_sizes (int or list[int] or tuple[int]): max sample size,
+                can be defined separately for src and tgt (then list or tuple)
+
+        Returns:
+            np.array: filtered sample array
+            list: list of removed indices
+        """
+        return data_utils.filter_paired_dataset_indices_by_size(
+            self.src_sizes,
+            self.tgt_sizes,
+            indices,
+            max_sizes,
+        )
+
+    @property
+    def supports_fetch_outside_dataloader(self):
+        """Whether this dataset supports fetching outside the workers of the dataloader."""
+        return False
+
+    @property
+    def can_reuse_epoch_itr_across_epochs(self):
+        return False  # to avoid running out of CPU RAM
+
+    def set_epoch(self, epoch):
+        super().set_epoch(epoch)
+        self.epoch = epoch
diff --git a/espresso/tasks/speech_recognition_hybrid.py b/espresso/tasks/speech_recognition_hybrid.py
index a10b07ea52..d526a7bf9a 100644
--- a/espresso/tasks/speech_recognition_hybrid.py
+++ b/espresso/tasks/speech_recognition_hybrid.py
@@ -23,6 +23,7 @@
 from espresso.data import (
     AliScpCachedDataset,
     AsrChainDataset,
+    AsrK2Dataset,
     AsrXentDataset,
     AsrDictionary,
     AsrTextDataset,
@@ -74,6 +75,7 @@ class SpeechRecognitionHybridConfig(FairseqDataclass):
         },
     )
     feat_in_channels: int = field(default=1, metadata={"help": "feature input channels"})
+    use_k2_dataset: bool = field(default=False, metadata={"help": "if True use K2 dataset"})
     specaugment_config: Optional[str] = field(
         default=None,
         metadata={
@@ -146,6 +148,21 @@ class SpeechRecognitionHybridConfig(FairseqDataclass):
     max_epoch: int = II("optimization.max_epoch")  # to determine whether in trainig stage
 
 
+def get_k2_dataset_from_json(data_path, split, shuffle=True, pad_to_multiple=1, seed=1):
+    try:
+        from espresso.tools.lhotse.cut import CutSet
+    except ImportError:
+        raise ImportError("Please install Lhotse by `make lhotse` after entering espresso/tools")
+
+    data_json_path = os.path.join(data_path, "cuts_{}.json".format(split))
+    if not os.path.isfile(data_json_path):
+        raise FileNotFoundError("Dataset not found: {}".format(data_json_path))
+
+    cut_set = CutSet.from_json(data_json_path)
+    logger.info("{} {} examples".format(data_json_path, len(cut_set)))
+    return AsrK2Dataset(cut_set, shuffle=shuffle, pad_to_multiple=pad_to_multiple)
+
+
 def get_asr_dataset_from_json(
     data_path,
     split,
@@ -343,6 +360,7 @@ def __init__(self, cfg: DictConfig, dictionary):
         super().__init__(cfg)
         self.dictionary = dictionary
         self.feat_in_channels = cfg.feat_in_channels
+        self.use_k2_dataset = cfg.use_k2_dataset
         self.specaugment_config = cfg.specaugment_config
         self.num_targets = cfg.num_targets
         self.training_stage = (cfg.max_epoch > 0)  # a hack
@@ -402,6 +420,17 @@ def load_dataset(self, split, epoch=1, combine=False, **kwargs):
             paths = paths[:1]
         data_path = paths[(epoch - 1) % len(paths)]
 
+        if self.use_k2_dataset:
+            self.datasets[split] = get_k2_dataset_from_json(
+                data_path,
+                split,
+                shuffle=(split != self.cfg.gen_subset),
+                pad_to_multiple=self.cfg.required_seq_len_multiple,
+                seed=self.cfg.seed,
+            )
+            self.feat_dim = self.datasets[split].feat_dim
+            return
+
         self.datasets[split] = get_asr_dataset_from_json(
             data_path,
             split,
diff --git a/espresso/tools/Makefile b/espresso/tools/Makefile
index 81ca5fb0fc..ecef83a85d 100644
--- a/espresso/tools/Makefile
+++ b/espresso/tools/Makefile
@@ -1,5 +1,5 @@
 KALDI =
-PYTHON_DIR = ~/anaconda3/bin
+PYTHON_DIR = /export/b03/ywang/anaconda3/bin
 
 CXX ?= g++
 
@@ -30,6 +30,7 @@ kaldi:
 endif
 
 clean: openfst_cleaned
+	rm -rf lhotse
 	rm -rf pychain
 	rm -rf kaldi
 
@@ -79,3 +80,8 @@ pychain:
 	export PATH=$(PYTHON_DIR):$$PATH && \
 	cd pychain/openfst_binding && python3 setup.py install && \
 	cd ../pytorch_binding && python3 setup.py install
+
+.PHONY: lhotse
+lhotse:
+	test -d lhotse || git clone https://github.com/lhotse-speech/lhotse.git
+	export PATH=$(PYTHON_DIR):$$PATH && cd lhotse && pip install -e '.[dev]'