The invention provides a differentiated service realization method in wireless multimedia sensor networks under a coal mine. The method mainly comprises the steps of setting environment monitoring nodes, voice nodes and video nodes in the wireless multimedia sensor networks under the coal mine; designing different competition windows for sensing data business, voice business and video business according to different business quality demands of the sensing data business, the voice business and the video business; and transmitting data business to a ground monitoring center by the environment monitoring nodes, voice nodes and video nodes through channels of the wireless multimedia sensor networks according to set business transmission competition strategies based on various competition windows. According to the method, differentiated service of three kinds of business is realized, so different quality of service demands of the three kinds of business is ensured, the throughput capacity of the sensing data business and the voice business is increased by reducing the throughput capacity of the video business, and the time delay of the sensing data business and the voice business is reduced by increasing the time delay of the video business.