diff --git a/lib/ckb/api.rb b/lib/ckb/api.rb
index bbc63880..ee66df65 100644
--- a/lib/ckb/api.rb
+++ b/lib/ckb/api.rb
@@ -22,7 +22,7 @@ def initialize(host: CKB::RPC::DEFAULT_URL, mode: MODE::TESTNET)
       @rpc = CKB::RPC.new(host: host)
       if mode == MODE::TESTNET
         # Testnet system script code_hash
-        expected_code_hash = "0xc8b0772347016713ee8039d6b1d2f4b02803abdc4ea4e95677b0c5e8ff52ea3b"
+        expected_code_hash = "0x973bdb373cbb1d752b4ac006e2bb5bdcb63431ed2b6e394b22721c8906a2ad72"
         expected_type_hash = "0x9bd7e06f3ecf4be0f2fcd2188b23f1b9fcc88e5d4b65a8637b17723bbda3cce8"
         # For testnet chain, we can assume the second cell of the first transaction
         # in the genesis block contains default lock script we can use here.