Abstract: Understanding the spatial distribution characteristics and its influencing factors of cropland topsoil available potassium contents is essential for field nutrient management and soil resource conservation.Based on 4409 surface (0~20 cm) soil sample points collected during 2017-2019, the spatial distribution pattern and the influencing factors were analyzed in this study, using geostatistical methods, correlation analysis, analysis of variance and random forest model.The results showed that the available potassium contents in the study area ranged from 10.00 to 373.00 mg/kg, with a mean value of 110.48 mg/kg, which was lower than that of the national average (139 mg/kg); The coefficient of variation was 50.12%, which indicated a moderate spatial variability.The results of the semi-analysis of variance (ANOVA) showed that the best theoretical model was the exponential model.The model indicated a coefficient of determination of 0.975, the nugget effect of 62.9%, and the variability range of 23.5 km, which implied that the spatial distribution was determined by both structural factors and stochastic factors.The interpolation results showed that the cropland topsoil available potassium contents in the Sichuan Basin demonstrated a patchy spatial distribution pattern.Random forest model analysis showed that soil texture and pH were the most important factors affecting the cropland topsoil available potassium contents in the study area, followed by temperature and rainfall, while the effects of straw return, potash fertilizer application, topographic factors and soil type were relatively weak.The above results indicated that soil properties were the primary controlling factors for the spatial distribution of cropland topsoil available potassium contents.Under cultivation conditions, regulating soil texture and soil pH was the key to increase the cropland topsoil available potassium content.The formation of measurements such as straw return and fertilizer application should fully consider the effects of climate, topography and soil type.