In the context of rapid urbanization and global warming, the comprehensive demands of residents for urban living environments are increasing. The urban heat island effect is a typical ecological consequence of urbanization, which not only adversely affects human health but also restricts further urban development. This paper takes the central urban area of Hangzhou as the research object and evaluates its urban thermal environment and analyzes the influencing factors based on the Landsat 8 remote sensing data of 2013, 2020, and 2024. By applying the mean-standard deviation method, the urban thermal environment of the central urban area of Hangzhou is divided into five levels, and spatial analysis methods such as the transfer area proportion matrix are used to explore the spatiotemporal evolution of the urban thermal environment in the central urban area of Hangzhou between 2013 and 2024. Pearson correlation analysis is used to quantitatively study the relationship between various influencing factors and surface temperature, and the geographic detector is employed to identify the magnitude of influence of each driver and the impact of their interactions on the urban thermal environment in the central urban area of Hangzhou. The results show that from 2013 to 2024, the urban heat island effect in the central urban area of Hangzhou is worsening day by day, and the urban high-temperature areas show a trend of spreading from the city center to the suburbs. The influence of influencing factors such as population density and land use function mixing degree on the urban thermal environment shows a gradually weakening trend. These findings can help urban planning to grasp the dynamic change characteristics of the urban thermal environment more accurately, and then allocate resources scientifically and reasonably, providing targeted reference bases for the subsequent formulation of climate adaptation plans and strategies in the city.