Abstract: This study aimed to investigate the status and influencing factors of soil acidification in the main sugarcane-producing areas of Guangxi, China, and to provide a scientific basis for soil amelioration in sugarcane fields. A total of 54 surface soil samples (0~20 cm) were randomly collected from sugarcane fields across the main producing regions of Guangxi, covering 11 prefecture-level cities, with sampling intensity proportional to the local sugarcane cultivation area. Soil pH, soil organic carbon (SOC), pH buffering capacity (pHBC), exchangeable acidity, exchangeable aluminum, and exchangeable base cations were determined, and fitting relationships between soil pH and related soil properties were established. The soil pH ranged from 3.58 to 7.64, with a mean value of 5.37. Extremely strongly acidic soils (pH < 4.5), strongly acidic soils (4.5 ≤ pH < 5.0), and acidic soils (5.0 ≤ pH < 5.5) accounted for 26%, 20%, and 20% of the samples, respectively, indicating pronounced soil acidification in sugarcane fields. The SOC content ranged from 2.45 to 11.66 g/kg, with a mean of 8.62 g/kg, suggesting the coexistence of soil acidification and low fertility; however, no significant correlation was observed between soil pH and SOC. The pHBC varied from 0.5 to 85.7 mmol/(kg·pH unit), with 64% of the samples exhibiting values lower than 20 mmol/(kg·pH unit). Within the pHBC range of 0–30 mmol/(kg·pH unit), soil pH showed a significant positive linear correlation with pHBC. Exchangeable acidity ranged from 0.03 to 12.63 cmol/kg, with a mean value of 2.5 cmol/kg, and 74% of the samples had exchangeable acidity lower than 4.0 cmol/kg. The mean content of exchangeable calcium was 4.7 cmol/kg, and soil pH exhibited a significant nonlinear positive correlation with exchangeable calcium content. Overall, soil acidification is severe in the main sugarcane-producing areas of Guangxi, with 46% of the soils classified as strongly or extremely strongly acidic. The leaching loss of exchangeable calcium and the release of exchangeable hydrogen and aluminum ions are identified as the primary mechanisms driving soil acidification in sugarcane fields, providing a scientific basis for soil improvement and high-yield sugarcane production.