Set out from the connotation of the test and evaluation of the smoke jamming,the evaluation method of the smoke jamming was discussed.The evaluation rules of jamming effectiveness were presented.For electro-optical guided system,a jamming is effective or not is according to the changing of the tracking error,its guidance accuracy or its hit probability,The test result of the smoke screen's countering laser guided weapon under typical weather environment and different transmissivity of bomb release modes were given.The conclusion that the smoke is an effective jamming way was obtained.