In order to explore the effect of foliar application of boron fertilizer on citrus quality and soil bacterial community，field plot experiments were conducted to determine the boron content in citrus soil，leaf and fruit quality indicators(fruit diameter，single fruit weight，soluble solids content，titratable acid content，solid-acid ratio，and vitamin C content)and soil bacterial community under three levels of boron fertilizer application，i.e. 5 g/plant(0.25%)，10 g/plant(0.5%)and 15 g/plant(0.75%). The results showed that the appropriate application amount of boron fertilizer improved the quality of citrus fruit，and the high level of boron fertilizer treatment decreased the quality of citrus fruit. Among them，the effect of 0.25% boron fertilizer treatment was the best. Compared with CK(boron fertilizer application rate was 0)，the transverse diameter，longitudinal diameter and single fruit weight of citrus fruit were increased by 20.42%，6.21% and 24.62%，respectively；Soluble solids content was increased by 7.86%，titratable acid content was decreased by 16.03%，vitamin C content was increased by 9.07%. The application of boron fertilizer significantly increased the relative abundance of bacteria with pathogens resistant in soil，such as Kaistobacter，Rhodoplanes，Bacillus，and Sphingomonas(P<0.05). Among them，the 0.75% boron fertilizer application increased Kaistobacter from 0.42% to 2.12%，Rhodoplanes from 0.37% to 1.36%，and Sphingomonas from 0.18% to 0.59%. The Bacillus in the soil of 0.25% boron fertilizer application treatment was increased from 0.23% to 1.88%. These indicated that boron fertilizer spraying could affect the soil bacterial community. Under the premise of improving the quality of citrus and maximizing the utilization of resources，if the soil available boron content is insufficient in citrus planting and production，the boron fertilizer of 0.25 % boron acid solution(boron acid 5 g / plant)can be sprayed once at the fruit setting stage of citrus to meet the demand for boron nutrition of citrus trees and improve the quality of citrus.