diff --git a/src/3rdparty/monocypher/CMakeLists.txt b/src/3rdparty/monocypher/CMakeLists.txt
index 4b8a6b646a..170d409d35 100644
--- a/src/3rdparty/monocypher/CMakeLists.txt
+++ b/src/3rdparty/monocypher/CMakeLists.txt
@@ -1,3 +1,8 @@
+if (MSVC)
+    # Disable warning 4244 for monocypher.cpp
+    set_compile_flags(monocypher.cpp COMPILE_FLAGS /wd4244)
+endif()
+
 add_files(
     monocypher-ed25519.cpp
     monocypher-ed25519.h