Abstract: Objective To establish a method for measuring the photoelectric performance index (luminance response characteristic and luminance tolerance) of medical electronic endoscope.Methods Based on the clinical application and product features of medical electronic endoscope, the umbrella grayscale test chart and the adjustable gray scale test chart are designed and made from two aspects of distribution and density differential.Results The influence of gray scale arrangement, background illumination intensity and illumination spectrum on photoelectric performance measurement of electronic endoscope is verified by test.Conclusion It is a reference for the design analysis, evaluation and modification of electronic endoscope product photoelectric part, whether it is suitable for fast detection of umbels and more accurate gray scale test chart.