diff --git a/eth2/beacon/types/deposits.py b/eth2/beacon/types/deposits.py
index 5fb85fbb53..63c0bd3717 100644
--- a/eth2/beacon/types/deposits.py
+++ b/eth2/beacon/types/deposits.py
@@ -7,7 +7,7 @@
 )
 import ssz
 from ssz.sedes import (
-    List,
+    Vector,
     bytes32,
     uint64,
 )
@@ -24,7 +24,7 @@ class Deposit(ssz.Serializable):
 
     fields = [
         # Merkle branch in the deposit tree
-        ('proof', List(bytes32)),
+        ('proof', Vector(bytes32, 1)),
         # Index in the deposit tree
         ('index', uint64),
         # Deposit data
diff --git a/tests/eth2/beacon/conftest.py b/tests/eth2/beacon/conftest.py
index 28039f721e..0555e79de2 100644
--- a/tests/eth2/beacon/conftest.py
+++ b/tests/eth2/beacon/conftest.py
@@ -21,6 +21,7 @@
 )
 from eth2.beacon.types.attestation_data import AttestationData
 from eth2.beacon.types.crosslink_records import CrosslinkRecord
+from eth2.beacon.types.deposits import Deposit
 from eth2.beacon.types.deposit_data import DepositData
 from eth2.beacon.types.deposit_input import DepositInput
 from eth2.beacon.types.eth1_data import Eth1Data
@@ -76,6 +77,10 @@ def override_length(config):
     for key, value in historical_batch_vector_dict.items():
         HistoricalBatch._meta.container_sedes.field_name_to_sedes[key].length = value
 
+    Deposit._meta.container_sedes.field_name_to_sedes['proof'].length = (
+        config.DEPOSIT_CONTRACT_TREE_DEPTH
+    )
+
 
 @pytest.fixture(scope="session")
 def privkeys():