diff --git a/README.md b/README.md
index 6d3ec5f..597d429 100644
--- a/README.md
+++ b/README.md
@@ -535,6 +535,8 @@ Include `httplib.h` before `Windows.h` or include `Windows.h` by defining `WIN32
 #include <httplib.h>
 ```
 
+Note: Cygwin on Windows is not supported.
+
 License
 -------