The invention discloses a rain sheltering device of a switch cabinet. The rain sheltering device comprises a controller, an umbrella, a plurality of humidity sensors, a plurality of motors, a base and a top block; the umbrella includes a ring sleeve and an umbrella handle, the ring sleeve is sleeved on the umbrella handle, the umbrella is located above the base, the top block is fixedly arranged at the top of the umbrella, the top block is rotatably connected to the upper end of the umbrella handle, the base is fixedly arranged on the upper surface of the switch cabinet, the lower end of the umbrella is fixedly connected with the base or the switch cabinet, the motors are fixedly arranged in the base by surrounding the umbrella handle, output shafts of the motors penetrate the base to be connected with the ring sleeve rotatably, the humidity sensors are fixedly arranged on the switch cabinet and the top block, and the controller is located in the switch cabinet and is electrically connected with the humidity sensors and the motors. Whether humidity exceeds a set value or not is detected through the humidity sensors, the ring sleeve is driven to ascend by the motors to have the umbrella opened, an umbrella cover is opened to have the switch cabinet sheltered, and corrosion of the switch cabinet is delayed.