diff --git a/paimon-core/src/main/java/org/apache/paimon/mergetree/compact/PartialUpdateMergeFunction.java b/paimon-core/src/main/java/org/apache/paimon/mergetree/compact/PartialUpdateMergeFunction.java
index faddc8c4ec08..b24cf1edeb30 100644
--- a/paimon-core/src/main/java/org/apache/paimon/mergetree/compact/PartialUpdateMergeFunction.java
+++ b/paimon-core/src/main/java/org/apache/paimon/mergetree/compact/PartialUpdateMergeFunction.java
@@ -114,6 +114,7 @@ public void reset() {
         this.meetInsert = false;
         this.notNullColumnFilled = false;
         this.row = new GenericRow(getters.length);
+        this.latestSequenceNumber = 0;
         fieldAggregators.values().forEach(FieldAggregator::reset);
     }
 
diff --git a/paimon-core/src/test/java/org/apache/paimon/mergetree/compact/MergeFunctionTestUtils.java b/paimon-core/src/test/java/org/apache/paimon/mergetree/compact/MergeFunctionTestUtils.java
index d52d1fa1f854..4acea88b2d36 100644
--- a/paimon-core/src/test/java/org/apache/paimon/mergetree/compact/MergeFunctionTestUtils.java
+++ b/paimon-core/src/test/java/org/apache/paimon/mergetree/compact/MergeFunctionTestUtils.java
@@ -66,12 +66,10 @@ public static List<ReusingTestData> getExpectedForPartialUpdate(
                 expected.add(group.get(group.size() - 1));
             } else {
                 if (group.stream().noneMatch(data -> data.valueKind == RowKind.INSERT)) {
-                    // No insert: fill the pk and left nullable fields to null; sequenceNumber =
-                    // latest
+                    // No insert: fill the pk and left nullable fields to null; sequenceNumber = 0
+                    // because it's not updated
                     ReusingTestData last = group.get(group.size() - 1);
-                    expected.add(
-                            new ReusingTestData(
-                                    last.key, last.sequenceNumber, RowKind.DELETE, null));
+                    expected.add(new ReusingTestData(last.key, 0, RowKind.DELETE, null));
                 } else {
                     // get the last INSERT data because later DELETE data are ignored
                     group.stream()