diff --git a/CMakeLists.txt b/CMakeLists.txt
index 43530b463..b99c30af9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -666,8 +666,10 @@ install (FILES ${CMAKE_CURRENT_BINARY_DIR}/Eigen3Config.cmake
          DESTINATION ${CMAKEPACKAGE_INSTALL_DIR})
 
 # Add uninstall target
-add_custom_target ( uninstall
-    COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/EigenUninstall.cmake)
+if(NOT TARGET uninstall)
+  add_custom_target ( uninstall
+      COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/EigenUninstall.cmake)
+endif()
 endif()
 
 if (EIGEN_SPLIT_TESTSUITE)