The invention provides a waste heat recycling system of an annealing furnace. The waste heat recycling system comprises the annealing furnace, an air heat exchanger, a steam boiler, a hot water boiler, an exhaust fan, a combustion fan and a combustion air pipe. The annealing furnace comprises a heating section and a preheating section, the air heat exchanger is connected with the preheating section, the steam boiler is connected with the air heat exchanger, the hot water boiler is connected with the steam boiler, the exhaust fan is connected with the hot water boiler, the steam boiler is connected with a steam pipeline, the hot water boiler is connected with a hot water pipeline, the combustion fan is connected with the air heat exchanger, the combustion air pipe comprises a main pipe and a plurality of branch pipes communicated with the main pipe, one end of the main pipe is connected with the air heat exchanger, the branch pipes are connected with the heating section, and the main pipe is provided with an exhaust pipe and a pipe explosion prevention device. According to the waste heat recycling system of the annealing furnace, waste heat produced in the annealing process can be made full use of, and safety performance of the waste heat recycling system can be fully guaranteed.