PURPOSE: To enable superposed accidents like rear end collision to be prevented by providing a superposed accident preventing apparatus comprising a rotary lamp, an annunciator, a smoke candle etc. in the rear of an automobile and operating said apparatus with switchs arranged in a cab if necessary.

CONSTITUTION: On the rear of an automobile 1 is installed a superposed accident preventing apparatus 29 comprising a smoke candle caution danger signal instrument 14, a klaxon 15 for a following vehicle, rotary lamps 16, 17 capable of rotating on their own axes and revolving forward and backward, a caution danger signal apparatus 19 such as strobolight, etc. And said apparatus 29 is connected to a plurality of switches 6-9 arranged in the cab through a battery 3, a cabtire 4, a relay 5, etc. so that the respective apparatus 14-17, 19 can be operated by the respective switches 6-9. Thus, in emergency, warning sound 21, caution danger light rays 22, 23, fuming flame 28, etc. are generated to attract attention even from remote places easily under the conditions of dense fog, strong wind, rain, snow, etc. to prevent superposed accidents such as rear end collision.