diff --git a/libserial/CMakeLists.txt b/libserial/CMakeLists.txt
index ee72263..af10d90 100644
--- a/libserial/CMakeLists.txt
+++ b/libserial/CMakeLists.txt
@@ -7,6 +7,6 @@ if (MSVC)
     add_compile_options(/source-charset:utf-8)
 endif()
 
-include_directories(${CMAKE_SOURCE_DIR}/3rd/asio-1.30.2/include)
+include_directories(${CMAKE_CURRENT_SOURCE_DIR}/../3rd/asio-1.30.2/include)
 add_library(SerialOpr SHARED serial.h serial.cpp)
 target_compile_definitions(SerialOpr PRIVATE SERIALOPR_LIB DYNAMIC_DLL)
\ No newline at end of file