Abstract: The pH values of 1295 soil surface samples (0-20 cm) obtained from the project of Geochemical Survey on Soil Quality at the Lu’an-Huoshan region of Anhui Province were statistically analyzed in this study, and their spatial variability characteristics and influencing factors were discussed. The results showed that the pH of surface soil (0-20 cm) in the study area varied from 3.97 to 8.09, with an average value of 5.38. The soil samples of pH values within the range of 5.0 to 6.5 were about 90.57%, with acidic. The soil pH value in some areas was below 5.0, with strongly acidic. A small number of soil samples were moderately alkaline (7.5 to 8.5). As a whole, the distribution characteristics of pH value were higher in the north and lower in the south. The pH of surface soil in the whole region was normally distributed with a coefficient of variation of 7%, which belonged to the weak spatial variability. Geostatistical analysis results showed that the optimal theoretical model for the variation function of soil pH in the surface layer (0-20 cm) was an exponential model, and the nugget effect value was 0.423, indicating that it was affected by both human and structural factors and had a medium degree of spatial correlation. The variance analysis and regression analysis showed that the main controlling factors of spatial variability of soil pH in the study area were soil type, soil parent material, landform type, and land use pattern, which independently explained 19.1%, 11.1%, 9.3% and 2.5% of spatial variability of soil pH, respectively. In addition, the content of CaO, P, K₂O and S was negatively correlated with soil pH. Therefore, soil type and soil parent material were the main factors affecting Soil acidification in the Lu’an-Huoshan area of Anhui Province.