Under accelerated urbanization and high-intensity human activities, the natural wetlands distribution area (NWDA) in Minjiang River estuary faces the great challenge of a deteriorative urban thermal environment. This work aims to analyze the impact of land use/land cover (LULC) on the urban thermal environment and model wetland surface temperature disturbance characteristics during the process of urbanization. The study utilized the following methodological steps: (1) mapping of LULC spatial and temporal distribution through photo interpretation; (2) applying the mono-window algorithm to obtain the spatiotemporal patterns of land surface temperature (LST); (3) examining the correlation between LST and different LULC classes, normalized difference vegetation index (NDVI), normalized difference moisture index (NDMI), and normalized difference impervious surface index (NDISI); and (4) exploring wetland surface temperature characteristics based on profile analysis and regression models. The results showed that the LST pattern depended on the LULC distribution; the high LST zones were mainly observed in the center of Fuzhou city, and the low LST zones were mainly observed in forest and river areas. Moreover, the urban thermal environment was influenced by both LULC classes and urban growth types. Finally, the positive relationship between LST and NDISI indicated an amplifying effect of the impervious surface for wetland surface temperature, while vegetation with high liquid water attenuated the regional high temperature. The obtained conclusions are expected to be beneficial in improving the design and management of the urban thermal environment.