The invention discloses a sunlight-type heating adjustment device in a low-temperature environment, relates to the field of power online monitoring, and aims at solving a problem that the internal temperature of a thermal insulation box cannot be adjusted automatically. The device is disposed in the thermal insulation box, and is communicated with a heat collector. The thermal insulation box is communicated with the heat collector through a cold air inlet of the heat collector. When the temperature of the external environment is high, the hot air generated by the heat collector is directly discharged to the atmosphere, and the interior of the thermal insulation box is always communicated with the atmosphere. When the temperature of the external environment is low, the hot air generated by the heat collector directly enters the thermal insulation box, and the thermal insulation box is insulated with the atmosphere. The beneficial effects are that the purpose of automatically adjusting the temperature is achieved; the device does not waste energy, saves the electric energy, and is simple in structure. The device is suitable for the automatic adjustment of the internal temperature of the thermal insulation box.