diff --git a/backends/metax_gpu/cinn/cinn_interface.cc b/backends/metax_gpu/cinn/cinn_interface.cc
index a01bd0e67e..316888a81c 100644
--- a/backends/metax_gpu/cinn/cinn_interface.cc
+++ b/backends/metax_gpu/cinn/cinn_interface.cc
@@ -68,8 +68,15 @@ extern C_Status MetaxLaunchKernel(void* dev_ptr,
                                   void* stream);
 
 // --- From passes/pass_manager.cc ---
-// Applies custom graph optimization passes
-extern C_Status MetaxApplyCustomPass(void* dev_ptr, void* ir_module);
+// Applies a vendor-specific custom pass identified by name
+extern C_Status MetaxApplyCustomPass(void* dev_ptr,
+                                     const char* pass_name,
+                                     void* ir_func);
+
+// Queries the vendor's desired ordered pass pipeline
+extern C_Status MetaxQueryPassPipeline(void* dev_ptr,
+                                       char pass_names[][128],
+                                       int* count);
 
 // ============================================================
 // Interface Initialization
@@ -102,6 +109,7 @@ void InitCinnInterface(C_DeviceInterface* device_interface) {
 
   // 6. Register Compilation Strategy interface
   metax_cinn_impl.apply_custom_pass = MetaxApplyCustomPass;
+  metax_cinn_impl.query_pass_pipeline = MetaxQueryPassPipeline;
 
   // 7. Attach the populated dispatch table to the Paddle device interface
   if (device_interface) {
diff --git a/backends/metax_gpu/cinn/passes/pass_manager.cc b/backends/metax_gpu/cinn/passes/pass_manager.cc
index 15d73d0738..cf4e652130 100644
--- a/backends/metax_gpu/cinn/passes/pass_manager.cc
+++ b/backends/metax_gpu/cinn/passes/pass_manager.cc
@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include <cstring>
 #include <iostream>
 
 #include "paddle/phi/backends/device_ext.h"
@@ -20,10 +21,87 @@ namespace paddle {
 namespace custom_device {
 namespace metax {
 
-// Applies custom graph optimization passes.
-// Currently a no-op stub; returns success immediately.
-C_Status MetaxApplyCustomPass(void* dev_ptr, void* ir_module) {
-  // VLOG(3) << "[MetaX] MetaxApplyCustomPass called (No-op)";
+// ============================================================
+// MetaxApplyCustomPass
+// ============================================================
+// Called by the CINN framework when it encounters a pass name in the pipeline
+// that is NOT a built-in pass.  `ir_func` is a `cinn::ir::LoweredFunc*` cast
+// to void*.
+C_Status MetaxApplyCustomPass(void* dev_ptr,
+                              const char* pass_name,
+                              void* ir_func) {
+  std::string name(pass_name);
+
+  if (name == "MetaxDebugLogPass") {
+    // A trivial pass that simply logs the function pointer address.
+    // Demonstrates the custom-pass mechanism without modifying IR.
+    std::cout << "[MetaX] MetaxDebugLogPass: ir_func=" << ir_func << std::endl;
+    return C_Status::C_SUCCESS;
+  }
+
+  std::cerr << "[MetaX] Unknown custom pass: " << name << std::endl;
+  return C_Status::C_FAILED;
+}
+
+// ============================================================
+// MetaxQueryPassPipeline
+// ============================================================
+// Defines the ordered pass pipeline for MetaX GPU hardware.
+//
+// Rules:
+//   - Built-in pass names (understood by CINN) are executed by the framework.
+//   - Unknown names are forwarded to MetaxApplyCustomPass().
+C_Status MetaxQueryPassPipeline(void* dev_ptr,
+                                char pass_names[][128],
+                                int* count) {
+  // Full NVGPU-equivalent pipeline with one custom pass inserted.
+  static const char* kPipeline[] = {
+      "Simplify",
+      "EliminateInvariantLoop",
+      "RealizeCompositeReduce",
+      "ReindexTransposeBuffer",
+      "ReplaceCrossThreadReduction",
+      "ReplaceCrossBlockReduction",
+      "SetCudaAxisInfo",
+      "RemoveGpuForLoops",
+      "CudaSyncThreadsDropIfThenElse",
+      "TransBufferWithDynamicShape",
+      "SimplifyUnitBlock",
+      "MapExternCall",
+      "ExternCallMultiOutputShallowStore",
+      "Simplify",
+      "IfFusion",
+      "EntailLoopCondition",
+      // Vendor-defined custom pass: forwarded to MetaxApplyCustomPass().
+      "MetaxDebugLogPass",
+      "RearrangeLoadInstruction",
+      "VectorizeForTrans",
+      "Simplify",
+      "RemoveScheduleBlock",
+      "IfFold",
+      "LowerIntrin",
+      "PrepareBufferCastExprs",
+  };
+  static const int kPipelineSize =
+      static_cast<int>(sizeof(kPipeline) / sizeof(kPipeline[0]));
+
+  // If pass_names is null the caller only wants the count.
+  if (pass_names == nullptr) {
+    *count = kPipelineSize;
+    return C_Status::C_SUCCESS;
+  }
+
+  // Check buffer capacity.
+  if (*count < kPipelineSize) {
+    *count = kPipelineSize;
+    return C_Status::C_FAILED;
+  }
+
+  for (int i = 0; i < kPipelineSize; ++i) {
+    std::strncpy(pass_names[i], kPipeline[i], 127);
+    pass_names[i][127] = '\0';
+  }
+  *count = kPipelineSize;
   return C_Status::C_SUCCESS;
 }