In the last two decades, the earth has suffered unprecedented urban expansion. The object of this paper is to reveal the difference of thermal response of extremely high temperature in JINGJINTANG agglomeration in two urbanization stage by using WRF model and real-Synchronization Landsat data. And so does it for GTHA agglomeration. By comparison of the two differences, it well reflects Land Surface Temperature difference caused by the urbanization. For both agglomerations, urbanization has less impact on the urban center, while it has more impact on new urban. Jingjintang has stronger UHI extent which reached to 6°C –8°C than in the day while GTHA has less LST difference at night and more LST difference in the day comparing to Jingjintang. Overall, this method provided in this research can be used to analyze impacts on urban thermal environment and also used for thermal environment monitoring and prediction.