diff --git a/contrib/runtime/aer_runtime.cpp b/contrib/runtime/aer_runtime.cpp
index 2a4d65cc2f..0f8685b84e 100644
--- a/contrib/runtime/aer_runtime.cpp
+++ b/contrib/runtime/aer_runtime.cpp
@@ -76,6 +76,13 @@ complex_t *aer_release_statevector(void *handler) {
   return sv.move_to_buffer();
 };
 
+// u3 gate
+void aer_apply_u3(void *handler, uint_t qubit, double theta, double phi,
+                  double lambda) {
+  AER::AerState *state = reinterpret_cast<AER::AerState *>(handler);
+  state->apply_u(qubit, theta, phi, lambda);
+}
+
 // phase gate
 void aer_apply_p(void *handler, uint_t qubit, double lambda) {
   AER::AerState *state = reinterpret_cast<AER::AerState *>(handler);
diff --git a/contrib/runtime/aer_runtime_api.h b/contrib/runtime/aer_runtime_api.h
index 2e27a6fcc0..6d707e8db4 100644
--- a/contrib/runtime/aer_runtime_api.h
+++ b/contrib/runtime/aer_runtime_api.h
@@ -45,6 +45,9 @@ double complex aer_amplitude(void* state, uint_t outcome);
 // returned pointer must be freed in the caller
 double complex* aer_release_statevector(void* state);
 
+// u3 gate
+void aer_apply_u3(void* state, uint_t qubit, double theta, double phi, double lambda);
+
 // phase gate
 void aer_apply_p(void* state, uint_t qubit, double lambda);
 
diff --git a/releasenotes/notes/support_u3_runtime_api-42f013f111c319ff.yaml b/releasenotes/notes/support_u3_runtime_api-42f013f111c319ff.yaml
new file mode 100644
index 0000000000..72dec64c0b
--- /dev/null
+++ b/releasenotes/notes/support_u3_runtime_api-42f013f111c319ff.yaml
@@ -0,0 +1,4 @@
+---
+features:
+  - |
+    `aer_apply_u3` is added to `aer_runtime_api.h`