diff --git a/tensorflow/compiler/mlir/lite/tests/default_quant_params.mlir b/tensorflow/compiler/mlir/lite/tests/default_quant_params.mlir
index 31b6e7968cdede..7ddd4baaee5827 100644
--- a/tensorflow/compiler/mlir/lite/tests/default_quant_params.mlir
+++ b/tensorflow/compiler/mlir/lite/tests/default_quant_params.mlir
@@ -87,3 +87,27 @@ func @test_conv_2d_activation_and_bias(%arg0: tensor<1x224x224x3xf32>, %arg1: te
 // CHECK: %[[dq:.*]] = "tfl.dequantize"(%[[conv]]) : (tensor<1x112x112x32x!quant.uniform<u8:f32, 0.0078431372549019607:128>>)
 // CHECK: return %[[dq]]
 }
+
+// CHECK-LABEL: test_region
+func @test_region(%arg0: tensor<128x128x!quant.uniform<u8:f32, 0.1:127>>,
+    %arg1: tensor<1x!quant.uniform<u8:f32, 0.2:127>>, %arg2: tensor<1x!quant.uniform<u8:f32, 0.4:127>>,
+    %arg3: tensor<1xi32>) -> (tensor<128x128x!quant.uniform<u8:f32, 0.2:125>>) {
+  %0 = "tfl.dequantize"(%arg0) : (tensor<128x128x!quant.uniform<u8:f32, 0.1:127>>) -> tensor<128x128xf32>
+  %1 = "tfl.dequantize"(%arg1) : (tensor<1x!quant.uniform<u8:f32, 0.2:127>>) -> tensor<1xf32>
+  %2 = "tfl.dequantize"(%arg2) : (tensor<1x!quant.uniform<u8:f32, 0.4:127>>) -> tensor<1xf32>
+  %3 = "tfl.custom_tf"(%0, %1, %2, %arg3) ( {
+  ^bb0(%a1: tensor<128x128xf32>, %a2: tensor<1xf32>, %a3: tensor<1xf32>, %a4: tensor<1xi32>):  // no predecessors
+    %4 = "tf.LayerNorm"(%a1, %a2, %a3, %a4) {_tfl_quant_trait = "fully_quantizable", device = ""} : (tensor<128x128xf32>, tensor<1xf32>, tensor<1xf32>, tensor<1xi32>) -> tensor<128x128xf32>
+   "tfl.yield"(%4) : (tensor<128x128xf32>) -> ()
+  }) {_tfl_quant_trait = "fully_quantizable", device = ""} : (tensor<128x128xf32>, tensor<1xf32>, tensor<1xf32>, tensor<1xi32>) -> tensor<128x128xf32>
+  %4 = "tfl.quantize"(%3) {qtype = tensor<128x128x!quant.uniform<u8:f32, 0.2:125>>} : (tensor<128x128xf32>) -> tensor<128x128x!quant.uniform<u8:f32, 0.2:125>>
+  return %4 : tensor<128x128x!quant.uniform<u8:f32, 0.2:125>>
+
+// CHECK: "tfl.custom_tf"
+// CHECK-NEXT: ^bb0(%arg4: tensor<128x128xf32>, %arg5: tensor<1xf32>, %arg6: tensor<1xf32>, %arg7: tensor<1xi32>):  // no predecessors
+// CHECK-NEXT:   "tf.LayerNorm"(%arg4, %arg5, %arg6, %arg7) {_tfl_quant_trait = "fully_quantizable", device = ""} : (tensor<128x128xf32>, tensor<1xf32>, tensor<1xf32>, tensor<1xi32>) -> tensor<128x128xf32>
+// CHECK-NEXT:   "tfl.yield"
+// CHECK-NEXT: }) {_tfl_quant_trait = "fully_quantizable", device = ""} :
+// CHECK-SAME: (tensor<128x128xf32>, tensor<1xf32>, tensor<1xf32>, tensor<1xi32>) -> tensor<128x128xf32>
+}
+
diff --git a/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc b/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc
index c4474d4c6e37ed..b66d46b6a3fea1 100644
--- a/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc
+++ b/tensorflow/compiler/mlir/lite/transforms/default_quant_params.cc
@@ -109,10 +109,10 @@ void DefaultQuantParamsPass::runOnFunction() {
   }
 
   func.walk([&](Operation *op) {
-    if (op->hasTrait<OpTrait::IsTerminator>() ||
-        op->hasTrait<OpTrait::quant::NoQuantizableResult>() ||
-        llvm::isa<quant::QuantizeCastOp, quant::DequantizeCastOp>(op))
+    if (quant::IsOpNotQuantizable(op) ||
+        op->getParentOfType<TFL::CustomTfOp>()) {
       return;
+    }
 
     for (auto res : op->getResults()) {
       if (UsedAsBias(res)) {