A field experiment was carried out to study the effects of corn straw mulching (JF), white film mulching (BF), black film mulching (HM), horticultural mulching (YD), and clean cultivation as the control (CK) on soil physio-chemical properties, soil bacterial community characteristics, and citrus quality of the citrus orchards on the Yunnan-Guizhou Plateau. The results showed that compared with CK treatment, the yield, single fruit weight, juice rate, edible rate, vitamin C content, and soluble solids of citrus increased under different mulching treatments. In contrast, the titratable acid content of citrus decreased, resulting in increasing the solid-acid ratio of citrus. Among different types of mulching, the most significant effective treatment was JF. BF, HM, and YD decreased soil pH, while mulching treatments could increase soil temperature, water content, organic matter, and nutrient content. JF treatment exhibited the most obvious effect on the contents of soil organic matter, total nitrogen, total phosphorus, total potassium, available phosphorus, and available potassium. BF treatment significantly increased soil temperature. JF, HM, and YD treatments significantly increased Chao1 index and Observed species index. At the phylum level, the mulching increased the relative abundance of Actinobacteria and decreased the relative abundance of Bacteroidetes. At the genus level, the relative abundance of Acidothermus, Chujaibacter, Babeliales, Rhodobacter, and Dechloromonas were increased, but the relative abundance of Saccharimonadales, Dyadobacter, Chryseobacterium, Sporosarcina and Comamonas were decreased. In addition, the mulching treatments made a simple and stable soil bacterial symbiosis network. Redundancy analysis showed that soil total nitrogen and Rhodobacter were key factors in improving the yield and quality of citrus, explaining 45.67% and 39.40% variations in the yield and quality of citrus, respectively. Variance decomposition analysis showed that the combined effect of soil physio-chemical properties and bacterial community contributed most to the improvement of citrus yield and quality, with an explanation rate of 45.0%. In conclusion, the mulching treatments can effectively improve soil physio-chemical properties and the level of soil nutrient supply, optimize bacterial community structure, and improve citrus yield and quality. Of these, the corn straw mulching can be preferentially used as a surface mulching measure for citrus orchard soil on the Yunnan-Guizhou Plateau.