Considering that manual adjustment of the light guide plate illumination for civil aircraft cockpit not only increases the pilot's workload, but also has difficulties in precisely controlling the brightness of light guide plate according to cockpit light environment, we studied the self adaptive dimming control technology for the lighting system of light guide plate. Ambient light distribution in different areas was established through cockpit 3D modeling and SPEOS optical simulation, the layout of ambient light sensors was determined, and the brightness dimming curve model was established through ergonomics test for cockpit light environment and statistical analysis of confidence interval. Based on which, an ideal model of self adaptive dimming control for the light guide plate illumination was proposed, which provides a theoretical basis for application of the research result in the field of aircraft design.