Obtaining high-quality images of organisms is critical to life sciences research, but imaging optical system and organism itself contain aberrations, leading to reduced resolution and contrast. Since aberrations introduced by different organisms are different and may change with time, they cannot be compensated by conventional optical design methods. Adaptive optics, originating in astronomical imaging observations, has the ability to overcome the effects of dynamic aberrations, and can therefore be used to improve imaging quality in biological imaging. Conventional adaptive optics typically has a wavefront sensor (such as Shack-Hartmann sensor) to measure wavefront errors. Recently developed wavefront sensorless adaptive optics (WSLAO) has got rid of dedicated wavefront sensors, so the system structure can be simplified and the cost is reduced. WSLAO can also overcome some limitations of traditional adaptive optics and has good application prospects. In this paper, the working principle of WSLAO is given at first. Then the applications of this technology in fundus imaging and fluorescence microscopy are discussed and the future development trend is proposed.