With global warming and the accelerated urbanization-process, the impact of urban high temperature-induced disaster becomes more and more distinct. By using the WRF/UCM model, the influence of two factors of existence of the West Lake and urbanization-process on high temperature over Hangzhou is investigated. Three experiments were designed: Experiment 1 is set-up as the control run with the land-use data in 2010 is adopted. In experiment 2, the West Lake is replaced by paddy field and other parameters are the same as that in the first run;In experiment 3, the land-use data in 2000 is adopted and other parameters are the same as that in the first run. While comparing the result of experiment 1 run with that of experiment 2, it can be concluded that the West Lake is able to reduce high temperature in daytime and prompt high temperature at night, respectively. Generally, the West Lake contributes to enhance high temperature over Hangzhou. While comparing the result of experiment 1 with that of experiment 3, it can be found that urban heat island effect (UHIE) induced by the urbanization-process helps to intensify high temperature over Hangzhou and enlarge the high temperature area. UHIE prompts high temperature both in daytime and at nighttime, and exerts more important influence in daytime.