diff --git a/modules/ECMAddTests.cmake b/modules/ECMAddTests.cmake
--- a/modules/ECMAddTests.cmake
+++ b/modules/ECMAddTests.cmake
@@ -114,6 +114,10 @@
   add_test(NAME ${_testname} COMMAND ${_targetname})
   target_link_libraries(${_targetname} ${ARG_LINK_LIBRARIES})
   ecm_mark_as_test(${_targetname})
+  if (CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+    set(_plugin_path $ENV{QT_PLUGIN_PATH})
+    set_property(TEST ${_testname} PROPERTY ENVIRONMENT QT_PLUGIN_PATH=${CMAKE_LIBRARY_OUTPUT_DIRECTORY}:${_plugin_path})
+  endif()
   if (ARG_TARGET_NAME_VAR)
     set(${ARG_TARGET_NAME_VAR} "${_targetname}" PARENT_SCOPE)
   endif()