The paper aims to investigate the influence of typhoon on the design wind speed in Guangdong coastal area, and to develop technological process for improving wind zone atlas for transmission line. An optimization method based on the YanMeng typhoon wind field model and Poisson-Gumbel distribution is proposed. Based on the historical maximum wind speed data and design wind speed results of 23 coastal stations in Guangdong, the performance of the typhoon wind field model is verified. The results indicate that typhoon is the main source of maximum wind speed in coastal areas of Guangdong. The consistent temporal variation of the maximum wind speed are shown between simulation and observation data, with the mean absolute error (MAE) of 0~2 m/s. Compared with wind zone atlas of design wind speed for coastal power grid of Guangdong, similar spatial distribution characteristics are reproduced by typhoon wind field model with higher spatial resolution. It is reasonable to apply typhoon wind field model in wind zone atlas distribution simulation and optimization in coastal areas.