diff --git a/include/grpc/impl/codegen/port_platform.h b/include/grpc/impl/codegen/port_platform.h
index 9640ab60089..b8aa199aa84 100644
--- a/include/grpc/impl/codegen/port_platform.h
+++ b/include/grpc/impl/codegen/port_platform.h
@@ -150,7 +150,11 @@
 #elif defined(ANDROID) || defined(__ANDROID__)
 #define GPR_PLATFORM_STRING "android"
 #define GPR_ANDROID 1
+#ifdef _LP64
+#define GPR_ARCH_64 1
+#else /* _LP64 */
 #define GPR_ARCH_32 1
+#endif /* _LP64 */
 #define GPR_CPU_LINUX 1
 #define GPR_GCC_SYNC 1
 #define GPR_GCC_TLS 1