diff --git a/Source/Core/VideoBackends/D3D/Render.cpp b/Source/Core/VideoBackends/D3D/Render.cpp
index 31ab07ddaa..5db7b8b4ec 100644
--- a/Source/Core/VideoBackends/D3D/Render.cpp
+++ b/Source/Core/VideoBackends/D3D/Render.cpp
@@ -486,8 +486,8 @@ void Renderer::SetViewport()
 	Ht = (Y + Ht <= GetTargetHeight()) ? Ht : (GetTargetHeight() - Y);
 
 	D3D11_VIEWPORT vp = CD3D11_VIEWPORT(X, Y, Wd, Ht,
-		(xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f,
-		xfmem.viewport.farZ / 16777216.0f);
+		std::max(0.0f, std::min(1.0f, (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f)),
+		std::max(0.0f, std::min(1.0f, xfmem.viewport.farZ / 16777216.0f)));
 	D3D::context->RSSetViewports(1, &vp);
 }