diff --git a/include/mlir-hlo/Dialect/mhlo/IR/hlo_ops.td b/include/mlir-hlo/Dialect/mhlo/IR/hlo_ops.td
index 80fd274..33c8ecd 100644
--- a/include/mlir-hlo/Dialect/mhlo/IR/hlo_ops.td
+++ b/include/mlir-hlo/Dialect/mhlo/IR/hlo_ops.td
@@ -1471,12 +1471,12 @@ def HLO_CustomCallOp: HLO_Op<"custom_call", []> {
     See https://www.tensorflow.org/xla/operation_semantics#customcall.
   }];
   let arguments = (ins
-    Variadic<HLO_Tensor>:$args,
+    Variadic<HLO_TensorOrTuple>:$args,
     StrAttr:$call_target_name,
     DefaultValuedAttr<BoolAttr, "false">:$has_side_effect,
     DefaultValuedAttr<StrAttr, "">:$backend_config
   );
-  let results = (outs Variadic<HLO_Tensor>);
+  let results = (outs Variadic<HLO_TensorOrTuple>);
   let hasCustomHLOConverter = 1;
 }