The invention provides a power distribution cabinet door with a high-temperature self-locking function, which comprises a power distribution cabinet, sliding grooves, a cabinet door and pulleys, the sliding grooves are formed in the upper part and the lower part of one side in the power distribution cabinet, the cabinet door is slidably arranged between the two sliding grooves through the pulleys, and a self-locking structure and a sealing structure are respectively arranged in the power distribution cabinet. The self-locking structure comprises a groove A, a glass tube, a sliding block A, a triangular clamping block A, a groove C, a clamping block and a triangular clamping block C. The groove A is formed in one side of the power distribution cabinet in a hollow mode, the glass tube is fixedly installed at the bottom of the groove A, and the sliding block A is connected into the groove A through a spring. Through arrangement of a groove A, a glass tube, a sliding block A, a triangular clamping block A, a groove C, a clamping block and a triangular clamping block C, the glass tube can be heated and broken when a fire disaster occurs outside, so that a series of linkage reactions occur, the clamping block extends out to block a pulley at a cabinet door, flame cannot enter the power distribution cabinet to damage the power distribution cabinet, and the safety is improved.