In order to further elucidate the morphological process mechanism of anther dehiscence in rice，the difference of morphological characteristics of anthers and filaments between the wild type male sterile line V20A and its maintainer line V20B were detailed compared by using fluorescence microscopy，semi thin sectioning and scanning electron microscope. Results indicated that the normally open stomata distributed in intermicrosporangia 2 (IMS2) and the keratinized epidermal cells of anther guaranteed normally water loss，the “gas plug” in the rapidly elongated filaments, which formed due to rapid transpiration，was the origin of “driving force” to reversed pull the fiber layer on both sides of intermicrosporangia 1 (IMS1) during anther dehiscence, non–uniform thickening of inside and outside the wall of fiber layer determined the direction of dehisced force, and the “V” type of secondary thickening in surface fibrous layer of anther determined the position and order of dehiscence in anther.