The invention discloses an explosion-proof high and low temperature damp and heat test device, relating to the technical field of high concentration combustible gas sensor online climate testing. Thedevice mainly comprises four parts: an explosion-proof box body, an indirect heating refrigerating system, an air exchange system and a control circuit, wherein the explosion-proof box body is an inside-outside dual-layer shell, a box door is provided with an observation window and a security lock, the observation window is sealed for many layers, an LED lamp is installed in the box body, an explosion-proof methane gas sensor and a temperature sensor are installed in the LED lamp, the indirect heating refrigerating system comprises an evaporator, a humidifying water tray and a refrigerating unit, a heating unit, a humidifying unit, and a silicon oil tank, the air exchange system comprises an air supply system supplying air for the interior of the explosion-proof box body and an exhaust fanat the top of the box body, and the control circuit is arranged at the back of the box body and is a circuit safe in nature. The explosion-proof high and low temperature damp and heat test device protects operators in test, makes online environment measurement test more reliable, and controls methane gas concentration so as not to cause explosion.