By using adaptive optics technology, two sets of high-resolution imaging systems for living human retina have been developed. High-resolution imaging of living human retina in scale of cell is realized. In these systems, two novel types of 19- and 37-element small PZT deformable mirrors are used as wavefront correctors respectively, wavefront errors are measured by Hartman-Shack wavefront sensors, light of diode laser reflected from the eye retina is used as the beacon for wavefront sensing, After the wavefront error of human eye has been corrected by the adaptive optics system under the control of a computer, a flash lamp is triggered to illuminate the retina, the high resolution images are captured by a CCD camera. The residual errors are less than λ/6 and λ/10 respectively. The corresponding resolutions at retina are 3.4 μm and 2.6 μm respectively, approaching the diffraction limit. Experiments show that the resolution of the 37-element system is better than the 19-element system.