The invention relates to the field of power distribution cabinets, in particular to a high-and-low-voltage power distribution cabinet comprising universal wheels, a storage box, a sealing ring, a limiting structure, a fixation structure, a sunshade structure, a heat dissipation structure and a mounting structure. The universal wheels for movement are arranged at four corners of the bottom end of the storage box; the mounting structure being used for fixing an electrical instrument and being in rotation connection with the storage box is arranged inside the storage box; and the fixation structure that has a rectangular structure and cooperates with the sealing ring for sealing is arranged at the top of the storage box. The limiting structure is arranged between the fixation structure and the storage box; the sunshade structure for shading is arranged at the side wall of the fixation structure; and the heat dissipating structure for dissipating heat and removing dust is arranged on the side wall of the storage box. According to the invention, the electrical instruction is installed by the mounting structure that has a cooling accommodation cavity and is in rotation connection with the storage box; the contact area between the instrument and the air is increased; the electrical instrument can be dismounted and repaired conveniently when having any problem; and thus the maintenanceof the high-and-low-voltage power distribution cabinet becomes convenient and quick.