diff --git a/eth_typing/__init__.py b/eth_typing/__init__.py
index 29d13fc..a83dd22 100644
--- a/eth_typing/__init__.py
+++ b/eth_typing/__init__.py
@@ -3,6 +3,7 @@
     TypeStr,
 )
 from .bls import (  # noqa: F401
+    BLSPrivateKey,
     BLSPubkey,
     BLSSignature,
 )
diff --git a/eth_typing/bls.py b/eth_typing/bls.py
index f2ef413..785e670 100644
--- a/eth_typing/bls.py
+++ b/eth_typing/bls.py
@@ -3,4 +3,5 @@
 )
 
 BLSPubkey = NewType('BLSPubkey', bytes)  # bytes48
+BLSPrivateKey = NewType('BLSPrivateKey', int)
 BLSSignature = NewType('BLSSignature', bytes)  # bytes96