diff --git a/paddle/phi/api/include/compat/c10/core/ScalarType.h b/paddle/phi/api/include/compat/c10/core/ScalarType.h
index 97267e23089a4d..8d12bc13ab1ac1 100644
--- a/paddle/phi/api/include/compat/c10/core/ScalarType.h
+++ b/paddle/phi/api/include/compat/c10/core/ScalarType.h
@@ -80,6 +80,33 @@ inline bool isComplexType(ScalarType t) {
           t == ScalarType::ComplexDouble);
 }
 
+inline bool isBitsType(ScalarType t) {
+  return t == ScalarType::Bits1x8 || t == ScalarType::Bits2x4 ||
+         t == ScalarType::Bits4x2 || t == ScalarType::Bits8 ||
+         t == ScalarType::Bits16;
+}
+
+inline bool isBarebonesUnsignedType(ScalarType t) {
+  return t == ScalarType::UInt1 || t == ScalarType::UInt2 ||
+         t == ScalarType::UInt3 || t == ScalarType::UInt4 ||
+         t == ScalarType::UInt5 || t == ScalarType::UInt6 ||
+         t == ScalarType::UInt7 || t == ScalarType::UInt16 ||
+         t == ScalarType::UInt32 || t == ScalarType::UInt64;
+}
+
+inline ScalarType toQIntType(ScalarType t) {
+  switch (t) {
+    case ScalarType::Byte:
+      return ScalarType::QUInt8;
+    case ScalarType::Char:
+      return ScalarType::QInt8;
+    case ScalarType::Int:
+      return ScalarType::QInt32;
+    default:
+      return t;
+  }
+}
+
 inline bool isSignedType(ScalarType t) {
 #define CASE_ISSIGNED(name)     \
   case ScalarType::name:        \
@@ -177,6 +204,57 @@ inline bool isSignedType(ScalarType t) {
   return false;  // Unreachable, but satisfies compiler
 }
 
+inline bool isUnderlying(ScalarType type, ScalarType qtype) {
+  return type == toUnderlying(qtype);
+}
+
+inline ScalarType toRealValueType(ScalarType t) {
+  switch (t) {
+    case ScalarType::ComplexHalf:
+      return ScalarType::Half;
+    case ScalarType::ComplexFloat:
+      return ScalarType::Float;
+    case ScalarType::ComplexDouble:
+      return ScalarType::Double;
+    default:
+      return t;
+  }
+}
+
+inline ScalarType toComplexType(ScalarType t) {
+  switch (t) {
+    case ScalarType::BFloat16:
+      return ScalarType::ComplexFloat;
+    case ScalarType::Half:
+      return ScalarType::ComplexHalf;
+    case ScalarType::Float:
+      return ScalarType::ComplexFloat;
+    case ScalarType::Double:
+      return ScalarType::ComplexDouble;
+    case ScalarType::ComplexHalf:
+      return ScalarType::ComplexHalf;
+    case ScalarType::ComplexFloat:
+      return ScalarType::ComplexFloat;
+    case ScalarType::ComplexDouble:
+      return ScalarType::ComplexDouble;
+    default:
+      TORCH_CHECK(false, "Unknown Complex ScalarType for ", t);
+  }
+}
+
+inline bool canCast(const ScalarType from, const ScalarType to) {
+  if (isComplexType(from) && !isComplexType(to)) {
+    return false;
+  }
+  if (isFloatingType(from) && isIntegralType(to, false)) {
+    return false;
+  }
+  if (from != ScalarType::Bool && to == ScalarType::Bool) {
+    return false;
+  }
+  return true;
+}
+
 }  // namespace c10
 
 namespace at {
diff --git a/paddle/phi/api/include/compat/torch/headeronly/core/ScalarType.h b/paddle/phi/api/include/compat/torch/headeronly/core/ScalarType.h
index b51842d83fb963..7e6fd9670e1ec0 100644
--- a/paddle/phi/api/include/compat/torch/headeronly/core/ScalarType.h
+++ b/paddle/phi/api/include/compat/torch/headeronly/core/ScalarType.h
@@ -313,4 +313,25 @@ inline std::ostream& operator<<(std::ostream& stream, ScalarType scalar_type) {
   return stream << toString(scalar_type);
 }
 
+inline bool isQIntType(ScalarType t) {
+  return t == ScalarType::QInt8 || t == ScalarType::QUInt8 ||
+         t == ScalarType::QInt32 || t == ScalarType::QUInt4x2 ||
+         t == ScalarType::QUInt2x4;
+}
+
+inline ScalarType toUnderlying(ScalarType t) {
+  switch (t) {
+    case ScalarType::QUInt8:
+    case ScalarType::QUInt4x2:
+    case ScalarType::QUInt2x4:
+      return ScalarType::Byte;
+    case ScalarType::QInt8:
+      return ScalarType::Char;
+    case ScalarType::QInt32:
+      return ScalarType::Int;
+    default:
+      return t;
+  }
+}
+
 }  // namespace c10
diff --git a/test/cpp/compat/c10_ScalarType_test.cc b/test/cpp/compat/c10_ScalarType_test.cc
index 6a3bbc9b77fff9..d85326b7726a57 100644
--- a/test/cpp/compat/c10_ScalarType_test.cc
+++ b/test/cpp/compat/c10_ScalarType_test.cc
@@ -151,3 +151,78 @@ TEST(ScalarTypeTest, RestoredCompatScalarTypesKeepSourceLevelSemantics) {
   EXPECT_TRUE(c10::isFloat8Type(c10::ScalarType::Float8_e8m0fnu));
   EXPECT_TRUE(c10::isReducedFloatingType(c10::ScalarType::Float4_e2m1fn_x2));
 }
+
+TEST(ScalarTypeTest, HelperPredicatesAndConversionsMatchPyTorchBehavior) {
+  EXPECT_TRUE(c10::isQIntType(c10::ScalarType::QInt8));
+  EXPECT_TRUE(c10::isQIntType(c10::ScalarType::QUInt8));
+  EXPECT_TRUE(c10::isQIntType(c10::ScalarType::QInt32));
+  EXPECT_TRUE(c10::isQIntType(c10::ScalarType::QUInt4x2));
+  EXPECT_TRUE(c10::isQIntType(c10::ScalarType::QUInt2x4));
+  EXPECT_FALSE(c10::isQIntType(c10::ScalarType::Float));
+
+  EXPECT_TRUE(c10::isBitsType(c10::ScalarType::Bits1x8));
+  EXPECT_TRUE(c10::isBitsType(c10::ScalarType::Bits2x4));
+  EXPECT_TRUE(c10::isBitsType(c10::ScalarType::Bits4x2));
+  EXPECT_TRUE(c10::isBitsType(c10::ScalarType::Bits8));
+  EXPECT_TRUE(c10::isBitsType(c10::ScalarType::Bits16));
+  EXPECT_FALSE(c10::isBitsType(c10::ScalarType::Int));
+
+  EXPECT_TRUE(c10::isBarebonesUnsignedType(c10::ScalarType::UInt1));
+  EXPECT_TRUE(c10::isBarebonesUnsignedType(c10::ScalarType::UInt7));
+  EXPECT_TRUE(c10::isBarebonesUnsignedType(c10::ScalarType::UInt16));
+  EXPECT_TRUE(c10::isBarebonesUnsignedType(c10::ScalarType::UInt64));
+  EXPECT_FALSE(c10::isBarebonesUnsignedType(c10::ScalarType::Byte));
+  EXPECT_FALSE(c10::isBarebonesUnsignedType(c10::ScalarType::Int));
+
+  EXPECT_EQ(c10::toQIntType(c10::ScalarType::Byte), c10::ScalarType::QUInt8);
+  EXPECT_EQ(c10::toQIntType(c10::ScalarType::Char), c10::ScalarType::QInt8);
+  EXPECT_EQ(c10::toQIntType(c10::ScalarType::Int), c10::ScalarType::QInt32);
+  EXPECT_EQ(c10::toQIntType(c10::ScalarType::Float), c10::ScalarType::Float);
+
+  EXPECT_EQ(c10::toUnderlying(c10::ScalarType::QUInt8), c10::ScalarType::Byte);
+  EXPECT_EQ(c10::toUnderlying(c10::ScalarType::QUInt4x2),
+            c10::ScalarType::Byte);
+  EXPECT_EQ(c10::toUnderlying(c10::ScalarType::QUInt2x4),
+            c10::ScalarType::Byte);
+  EXPECT_EQ(c10::toUnderlying(c10::ScalarType::QInt8), c10::ScalarType::Char);
+  EXPECT_EQ(c10::toUnderlying(c10::ScalarType::QInt32), c10::ScalarType::Int);
+  EXPECT_EQ(c10::toUnderlying(c10::ScalarType::Float), c10::ScalarType::Float);
+
+  EXPECT_TRUE(
+      c10::isUnderlying(c10::ScalarType::Byte, c10::ScalarType::QUInt8));
+  EXPECT_TRUE(c10::isUnderlying(c10::ScalarType::Char, c10::ScalarType::QInt8));
+  EXPECT_TRUE(c10::isUnderlying(c10::ScalarType::Int, c10::ScalarType::QInt32));
+  EXPECT_FALSE(
+      c10::isUnderlying(c10::ScalarType::Byte, c10::ScalarType::QInt8));
+
+  EXPECT_EQ(c10::toRealValueType(c10::ScalarType::ComplexHalf),
+            c10::ScalarType::Half);
+  EXPECT_EQ(c10::toRealValueType(c10::ScalarType::ComplexFloat),
+            c10::ScalarType::Float);
+  EXPECT_EQ(c10::toRealValueType(c10::ScalarType::ComplexDouble),
+            c10::ScalarType::Double);
+  EXPECT_EQ(c10::toRealValueType(c10::ScalarType::Int), c10::ScalarType::Int);
+
+  EXPECT_EQ(c10::toComplexType(c10::ScalarType::Half),
+            c10::ScalarType::ComplexHalf);
+  EXPECT_EQ(c10::toComplexType(c10::ScalarType::Float),
+            c10::ScalarType::ComplexFloat);
+  EXPECT_EQ(c10::toComplexType(c10::ScalarType::Double),
+            c10::ScalarType::ComplexDouble);
+  EXPECT_EQ(c10::toComplexType(c10::ScalarType::BFloat16),
+            c10::ScalarType::ComplexFloat);
+  EXPECT_EQ(c10::toComplexType(c10::ScalarType::ComplexFloat),
+            c10::ScalarType::ComplexFloat);
+
+  EXPECT_TRUE(c10::canCast(c10::ScalarType::Int, c10::ScalarType::Long));
+  EXPECT_TRUE(c10::canCast(c10::ScalarType::Float, c10::ScalarType::Double));
+  EXPECT_TRUE(c10::canCast(c10::ScalarType::ComplexFloat,
+                           c10::ScalarType::ComplexDouble));
+  EXPECT_TRUE(c10::canCast(c10::ScalarType::Bool, c10::ScalarType::Int));
+
+  EXPECT_FALSE(
+      c10::canCast(c10::ScalarType::ComplexFloat, c10::ScalarType::Float));
+  EXPECT_FALSE(c10::canCast(c10::ScalarType::Float, c10::ScalarType::Int));
+  EXPECT_FALSE(c10::canCast(c10::ScalarType::Double, c10::ScalarType::Long));
+  EXPECT_FALSE(c10::canCast(c10::ScalarType::Int, c10::ScalarType::Bool));
+}