The effects of combined application of organic fertilizer with mixed Bacillus subtilis and gibberellin on the content of Candidatus Liberibacterasiaticus(CLas)，soil organic matter and soil microorganisms were compared in order to provide a scientific basis for the treatment of Huanglongbing and the improvement of citrus soil fertility. The Bacillus subtilis was isolated from endophytic bacteria in citrus leaves. The organic fertilizer combined with mixed Bacillus subtilis and 25 mg/L gibberellin treatment was used，while the other group doing without any treatment was used as the control. The contents of CLas，soil organic matter and soil microorganisms were compared and analyzed. Compared with the control group，the treatment group reduced CLas significantly，and the Ct value increased from the initial 25.10 to 31.46，soil organic matter and available potassium increased by 22.0% and 102.0%，respectively. The metabolites secreted by Bacillus complex could not only inhibit the growth of bacteria，but also optimize the soil structure by establishing dominant probiotics，promote root growth，effectively solve the problem of nutrient transport，and restore the state of diseased trees. Combined application of organic fertilizer with mixed Bacillus subtilis and gibberellin could significantly promote the improvement of citrus Huanglongbing，soil organic matter and available potassium.