The dynamics of urban biophysical descriptors, represented mainly by impervious surface, vegetation and open water, can affect the quality of urban thermal environment(UTE). With the progress of urbanization, Fuzhou City, located in the coastal area of southeastern China, has witnessed a significant UTE change, which led the city to have been reputed by media as the top of the three new "furnace cities" in China in 2007. To investigate the process of the city from a non-furnace city to a top furnace city in China, the dynamics of urban biophysical components of Fuzhou and the associated UTE change between 1976 and 2006 have been analyzed. The study focuses on the quantitative relationship between impervious surface and land surface temperature (LST) because the impervious surface has for many years been recognized as an indicator of the intensity of the UTE and, with the advent of urban sprawl, become a key issue in urban habitat health. The city's biophysical properties, e.g., impervious surface, vegetation and water, along with LST in 1976, 1986, 1996 and 2006 were retrieved from the Landsat MSS/TM images of the corresponding years. Three thematic indices Normalized Difference Impervious Surface Index (NDISI), Normalized Difference Vegetation Index (NDVI), and Modified Normalized Difference Water Index (MNDWI) were employed to extract features of impervious surface, vegetation and open water respectively from the satellite images. The spatial overlay and correlation analysis of these land surface features were then carried out. The results reveal the dynamics of the urban biophysical properties of the city in the 30 study years and their quantitative relationship to the UTE change. The area of urban impervious surface has significantly increased by 329% over the 30 years, which was only 20.45 km² in 1976 but remarkably increased to 87.89 km² in 2006. The cost of the increase in urban impervious surfaces is the considerable reduction of vegetation and open water coverage in the city area. The vegetation coverage in the urban area has decreased from 25% in 1976 to 9.8% in 2006. The replacement of the natural vegetation-dominated land surfaces by the impervious materials would have an impact on thermal environment of the city due to modification of heat energy balance. The study shows that the impervious surface has a positive exponential relationship with LST rather than a simple linear one, which suggests that the area with high percent impervious surface could accelerate LST rise and thus the urban heat island development. The study also found that the contribution of impervious surface to LST could equal or even exceed that of the sum of vegetation and water. On the whole, the significant urban biophysical-component changes of Fuzhou City during the study period have induced the strong urban heat island effect to the city, which led the city to have become the hottest one in China. The analysis shows that the increase and amalgamation of impervious surface patches, reduction and fragmentation of vegetation and water covers and poor urban ventilation are the main factors contributing to the formation of the "furnace city" of Fuzhou.