【Objective】Southeast Zhejiang is an important ecological barrier and an enrichment area of characteristic agricultural resources along the southeast coast of China, possessing substantial selenium resources. The spatial heterogeneity of soil selenium critically influences the planning of selenium-enriched agriculture and regional land resource management. However, systematic studies systematically elucidating the spatial distribution patterns of soil selenium and quantitatively assessing the contributions of its key driving factors within this specific region remain limited. .This study selected Wenzhou city, a highly representative area within this region characterized by complex geology and diverse land use, to achieve three primary objectives: 1) to precisely characterize the spatial distribution characteristics of selenium in surface soils, 2) to quantitatively evaluate the impacts of various natural and anthropogenic factors on soil Se content, and 3) to identify the dominant factors controlling its spatial variability. The findings aim to establish a scientific foundation for strategizing selenium-rich agricultural development and conducting accurate land quality assessment in Southeast Zhejiang.【Method】This investigation adhered to the technical specifications for 1:50,000 scale land quality geochemical surveys. A systematic sampling strategy was designed and implemented, collecting 25,753 surface soil samples (0–20 cm depth), with precise GPS positioning and documentation of site attributes (e.g., land use, parent material). Analytical methods included field geological surveys, laboratory determination of Se content (via atomic fluorescence spectrometry), soil nutrients (organic matter, total nitrogen), heavy metals, and pH. Data were analyzed using GIS spatial interpolation, correlation analysis, and multiple regression (stepwise approach) to explore spatial patterns and driving factors.【Result】The results revealed that the average selenium content in the surface soils of Wenzhou City was 0.32 mg·kg-1, with a range of 0.03 to 2.54 mg·kg?1.The coefficient of variation was 40%, indicating a moderate degree of variability. The selenium-rich soil (selenium content ≥ 0.4 mg·kg-1) accounted for 25.6% of the total area of the region. Geostatistical analysis demonstrated a strong spatial autocorrelation for soil Se, with an effective range of approximately 13.35 km based on the best-fitted exponential semivariogram model (R2 = 0.994). The spatial distribution exhibited a clear regional pattern, characterized by significantly higher Se levels predominantly in the central part of the city, encompassing low mountainous and hilly areas like Ouhai and Ruian, compared to the eastern and western regions. Statistical analyses confirmed that categorical variables, including stratigraphic unit, soil parent material, geomorphic type, soil type, land use type, and soil texture, all exerted statistically significant influences on the spatial variation of soil Se. Among these, parent material was identified as the most influential factor, with soils derived from intermediate-acid volcanic pyroclastics showing the highest Se content (0.457 mg·kg-1). Regarding soil physicochemical properties, Se content was significantly negatively correlated with soil pH, whereas it showed significant positive correlations with soil organic matter, total nitrogen, and several heavy metals (e.g., As, Pb). Multiple regression analysis further pinpointed soil type, parent material, pH, and arsenic content as the dominant factors collectively explaining 39.1% of the total spatial variance in soil Se.【Conclusion】The spatial differentiation of surface soil selenium in Wenzhou City is the result of the combined action of multiple factors such as geological background, soil physical and chemical properties, and human activities. The results of this study can provide a scientific basis for regional land quality evaluation and the rational development and utilization of selenium-rich characteristic agriculture.