Abstract: According to the problem that details of medical DR image are buried,edge of image is vague,contrast of image is reduced.Method of medical DR image enhancement based on artificial fish swarm and cell membrane optimization is proposed.Otsu method is optimized by artificial fish swarm algorithm.Medical DR image is divided by optimized Otsu method.Divided some area is decomposed to high frequency strong area,high frequency week area and low frequency area by cell membrane optimization algorithm.High frequency strong area is treated with nonlinear enhancement,high frequency weak area and low frequency area are treated with histogram equalization enhancement,other area is treated with linear enhancement.Simulation experiment on this method shows that noise of medical DR image is eliminated,details of medical DR image is more clear,effectiveness and robustness with this method are both high.