The invention discloses an environment room working condition adjusting system which comprises an air conditioner cabinet, a cooling device, a secondary refrigerant freezing circulating pipeline and a secondary refrigerant thermocycling pipeline. The system can work at a temperature lowering state, a working condition stable state, a defrosting state, an after-defrosting recovery state and a temperature raising state. By switching control of the freezing circulating pipeline, the thermocycling pipeline and an air conditioner electric air brake, a proper cold source and a proper heat source can be provided for a freezing surface air cooler and a cold and heat surface air cooler of the air conditioner cabinet, and the stability of environment room temperature and humidity working conditions is guaranteed. Surface air cooler automatic defrosting under the low-temperature working conditions is achieved, environment room working condition stability during the defrosting process can be guaranteed, and long-time operation of the low-temperature working conditions is achieved. The cooling device of the system is provided with a heat recovery unit, waste heat recovery is used for controlling secondary refrigerant temperature, and energy-saving operation is achieved.