diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 055d540798ee..1c7157027c75 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -2339,6 +2339,14 @@ add_library(qgis_core ${LIBRARY_TYPE} ${QGIS_CORE_SRCS} ${QGIS_CORE_HDRS} ${QGIS
 
 target_precompile_headers(qgis_core PRIVATE $<$<COMPILE_LANGUAGE:CXX>:qgis.h>)
 
+set_target_properties(qgis_core PROPERTIES UNITY_BUILD ON)
+
+# Exclude below files because they include tiny_gltf.h with different #define settings
+set_source_files_properties(tiledscene/qgsgltfutils.cpp
+                            tiledscene/qgsquantizedmeshtiles.cpp
+                            tiledscene/qgstiledscenelayerrenderer.cpp
+                            PROPERTIES SKIP_UNITY_BUILD_INCLUSION ON)
+
 # Add meshoptimizer
 if(WITH_INTERNAL_MESHOPTIMIZER)
   target_sources(qgis_core PRIVATE