Abstract: In order to identify the key factors affecting the occurrence of tobacco bacterial wilt in soil, 24 tobacco-planting soil samples with different severities of the disease were collected from tobacco growing areas with typical tobacco bacterial wilt occurrence. The differences of physicochemical properties and bacterial community structures among the soil samples with different disease severities were systematically studied by using group comparison, canonical correspondence analysis, principal component analysis and minimum data set. The results showed that soil pH, exchangeable calcium (ECa), available manganese (AMn) and soil aeration porosity (SAP) decreased significantly with the increase of disease index, while soil moisture content and soil capillary capacity (SCC) increased significantly. The occurrence of tobacco bacterial wilt slightly affected the relative abundances of main soil bacteria at phylum level, and significantly reduced the OTUs of Sphingomonas, Solirubrobacter and Rhizobium. Comprehensive analysis indicated that SCC, pH, AMn, and OTUs of Sphingomonas and Rhizobium were the key factors affecting the occurrence of tobacco bacterial wilt, and their correlations with the disease index were significant (P < 0.05).