diff --git a/Inc/DirectXMath.h b/Inc/DirectXMath.h
index bc7451fc..f672f43c 100644
--- a/Inc/DirectXMath.h
+++ b/Inc/DirectXMath.h
@@ -86,6 +86,9 @@
 #define _XM_SSE_INTRINSICS_
 #elif defined(_M_ARM) || defined(_M_ARM64) || defined(_M_HYBRID_X86_ARM64) || defined(_M_ARM64EC) || __arm__ || __aarch64__
 #define _XM_ARM_NEON_INTRINSICS_
+#elif defined(__riscv)
+// RISC-V currently uses the existing scalar no-intrinsics implementation.
+#define _XM_NO_INTRINSICS_
 #elif !defined(_XM_NO_INTRINSICS_)
 #error DirectX Math does not support this target
 #endif
diff --git a/README.md b/README.md
index 60cabff6..66aff30e 100644
--- a/README.md
+++ b/README.md
@@ -77,6 +77,8 @@ copilot
 
 Officially the library is supported with Microsoft Visual C++ 2019 (16.11) or later, clang/LLVM v12 or later, and GCC 10 or later. It should also compile with the Intel C++ and MinGW compilers.
 
+On RISC-V targets, DirectXMath selects its existing scalar `_XM_NO_INTRINSICS_` implementation by default. This does not provide any RISC-V vector or assembly optimizations.
+
 When building with clang/LLVM or other GNU C compilers, the ``_XM_NO_XMVECTOR_OVERLOADS_`` control define is set because these compilers do not support creating operator overloads for the ``XMVECTOR`` type. You can choose to enable this preprocessor define explicitly to do the same thing with Visual C++ for improved portability.
 
 To build for non-Windows platforms, you need to provide a ``sal.h`` header in your include path. You can obtain an open source version from [GitHub](https://raw.githubusercontent.com/dotnet/runtime/main/src/coreclr/pal/inc/rt/sal.h).