Abstract: The land-sea temperature difference (LSTD) serves as a pivotal indicator of thermal contrast in the land-sea interface. Variations in this difference drive an acceleration of the water cycle, increase atmospheric moisture retention, and potentially trigger extreme precipitation events, thereby exerting a profound influence on both regional and global climatic patterns. In this study, Moderate-resolution Imaging Spectroradiometer (MODIS) remote sensing data and meteorological station observations spanning from 2001 to 2021 are employed to investigate the spatiotemporal characteristics of LSTD and extreme precipitation, as well as the relationships between them in eastern China and its three buffer zones of 100 km, 200 km and 300 km from the coastline to the land and sea. Results indicate that the LSTD was generally negative in eastern China, with the difference becoming smaller in the buffer zone as it approached the coastline. The variation in LSTD displayed a prevalent downward trend, and the most substantial decline was observed within the 100 km buffer zone. Spatially, the LSTD demonstrated a distinct upward trend north of 26°N, contrasting with a downward trend observed south of this latitudinal boundary. In eastern China, both the very wet day precipitation (R95p) and the number of extremely heavy precipitation days (R25) exhibited a non-significant upward trend, with the most pronounced increase occurring in the Yangtze River Delta urban agglomeration. Consecutive dry days (CDD) primarily showed a non-significant decreasing trend, while consecutive wet days (CWD) were characterized as a considerable upward trend only in the coastal area of the northern East China Sea. LSTD commonly correlated positively with R95p and R25 in eastern China, and the regions with significant positive correlation were mainly located in the northern Bohai Sea Area and south of 30°N. Moreover, LSTD generally exhibited a negative correlation with CDD and a positive correlation with CWD, but neither correlation was significant in eastern China. These findings offer new insights into the characteristics of land-sea warming disparities and their impacts on precipitation extremes in eastern China, providing crucial references for mitigating and adapting to climate change in this transitional zone between land and sea.