diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index 8550d98fcce..8b447661436 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -2542,7 +2542,7 @@ extern void up_ledoff(int led);
 <ul>
   <li>
     <p>
-    <b><code>include/nuttx/serial.h</code></b>.
+    <b><code>include/nuttx/serial/serial.h</code></b>.
     All structures and APIs needed to work with serial drivers are provided in this header file.
     </p>
   </li>