diff --git a/psbt.py b/psbt.py
index 8a4d62b..4cc9fd1 100644
--- a/psbt.py
+++ b/psbt.py
@@ -383,7 +383,7 @@ def __init__(self, inputs, outputs, tx_version=2, input_sequence=0xffffffff, loc
         # Construct a serialized psbt manually
         new_psbt_serialized = MAGIC_BYTES + HEAD_SEPARATOR + psbt.serialize_map(key=PSBT_GLOBAL_UNSIGNED_TX, \
         value=serialized_tx)  + DATA_SEPARATOR + (DATA_SEPARATOR*len(self.tx_inputs)) + \
-        (DATA_SEPARATOR*len(self.tx_inputs))
+        (DATA_SEPARATOR*len(self.tx_outputs))
         # Create the psbt object using the serialized psbt
         self.psbt = psbt.parse(BytesIO(new_psbt_serialized))