diff --git a/lib/ckb/api.rb b/lib/ckb/api.rb
index 7a4d4c67..84e19853 100644
--- a/lib/ckb/api.rb
+++ b/lib/ckb/api.rb
@@ -135,11 +135,11 @@ def get_live_cell(out_point, with_data = false)
     #
     # @return [String] tx_hash
     def send_transaction(transaction)
-      rpc.send_transaction(transaction.to_h)
+      rpc.send_transaction(transaction.to_raw_transaction_h)
     end
 
     def compute_transaction_hash(transaction)
-      rpc.compute_transaction_hash(transaction.to_h)
+      rpc.compute_transaction_hash(transaction.to_raw_transaction_h)
     end
 
     def compute_script_hash(script)
@@ -195,7 +195,7 @@ def get_peers_state
     #
     # @return [CKB::Types::DryRunResult]
     def dry_run_transaction(transaction)
-      result = rpc.dry_run_transaction(transaction.to_h)
+      result = rpc.dry_run_transaction(transaction.to_raw_transaction_h)
       Types::DryRunResult.from_h(result)
     end
 
diff --git a/lib/ckb/types/transaction.rb b/lib/ckb/types/transaction.rb
index 2fea9e5f..6401c987 100644
--- a/lib/ckb/types/transaction.rb
+++ b/lib/ckb/types/transaction.rb
@@ -76,6 +76,18 @@ def to_h
         hash
       end
 
+      def to_raw_transaction_h
+        {
+          version: Utils.to_hex(@version),
+          cell_deps: @cell_deps.map(&:to_h),
+          header_deps: @header_deps,
+          inputs: @inputs.map(&:to_h),
+          outputs: @outputs.map(&:to_h),
+          outputs_data: @outputs_data,
+          witnesses: @witnesses.map(&:to_h)
+        }
+      end
+
       def compute_hash
         raw_transaction_serializer = CKB::Serializers::RawTransactionSerializer.new(self)
         blake2b = CKB::Blake2b.new