The invention discloses an outdoor high-efficiency heat-dissipation electrical box, and the electrical box comprises a housing, a top cover, and an electrical column. The upper part of the outer peripheral wall of the housing is provided with an air inlet, and the center of the bottom wall of the housing is provided with an air outlet. The inner peripheral wall of the housing is provided with an air guide plate. The intersection of the arc surface, far from the electrical column, of the air inlet and the inner peripheral wall of the housing is provided with a tangent line. The inner peripheralwall of the housing is provided with a tangent line at the intersection, and the inclined angle between the two tangent lines is not less than 30 degrees. According to the invention, the electrical box employs a cylindrical housing, and the setting of the air guide plate enlarges the distribution area of a rotating air flow, and also enables the air flow in the housing to form a plurality of spiral eddy flows which are distributed in the peripheral direction, thereby improving the turbulence degree of the air flow, and greatly improving the heat dissipation effect.