A thermal treatment mesh belt furnace comprises a heating section, a quenching section, a cleaning section and a tempering section which are arranged in sequence, wherein the cleaning section is disconnected from the tempering section, and a push-pull connecting plate is arranged on the bottom wall of the tempering section, and can be communicated with the cleaning section and the tempering section, or disconnected from the cleaning section and the tempering section. According to the thermal treatment mesh belt furnace provided by the invention, the connection or the disconnection between the cleaning section and the tampering section can be achieved through the connecting plate, that workpieces enter into the tempering section for tempering treatment directly after cleaning can be avoided, product quality is ensured, the finished product ratio is increased, the structure is simple, and the realization is easy.