A method for reducing release of resistance genes during sludge anaerobic treatment includes controlling concentration of to-be-treated sludge in a concentration tank to be 12-20 g/L by sedimentation under gravity. The concentrated sludge is transferred to a supersonic pre-treatment device to proceed with supersonic pre-treatment. The supersonic pre-treatment is conducted for 5-30 minutes at a power of 0.1-0.5 kW and a frequency of 10-40 kHz. The pre-treated sludge is then transferred to an anaerobic treatment device for anaerobic treatment. The anaerobic treatment is conducted for 4-12 days at a temperature of 20-37° C. The release amount of resistance genes in the residual sludge and the supernatant liquid in the anaerobic treatment device is detected. A feedback dosage of an alkali liquid is fed into the anaerobic treatment device according to the release amount of the resistance genes, controlling a pH value to be 9.0-11.0 during the anaerobic treatment.