diff --git a/CMakeLists.txt b/CMakeLists.txt
index 54ecaca0aa..2bcd6bfed5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -49,7 +49,7 @@ set(INSTALL_INCLUDE_DIR include CACHE PATH
 #--- Declare C++ Standard -----------------------------------------------------
 
 set(CMAKE_CXX_STANDARD 17 CACHE STRING "")
-if(NOT CMAKE_CXX_STANDARD MATCHES "17")
+if(NOT CMAKE_CXX_STANDARD MATCHES "17|20")
   message(FATAL_ERROR "Unsupported C++ standard: ${CMAKE_CXX_STANDARD}")
 endif()
 message (STATUS "C++ standard: ${CMAKE_CXX_STANDARD}")