Distribution box top cover

A distribution box top cover comprises a cover body (1). An inclined top plane (1.1) with the height gradually decreasing from the rear side to the front side is formed on the cover body (1), a rear bent side (1.2) which faces vertically downwards is formed at the rear edge of the inclined top plane (1.1), lateral bent sides (1.3) which firstly face vertically downwards, then face horizontally inwards and at last face vertically upwards are formed at the left edge of the inclined top plane (1.1) and the right edge of the inclined top plane (1.1) respectively, a front bent side (1.4) which firstly faces vertically downwards, then faces horizontally inwards, later faces vertically upwards and at last faces horizontally outwards is also formed at the front edge of the inclined top plane (1.1), wherein the edge of the front bent side (1.4) is in lap joint with the inner wall of the vertical side which firstly faces vertically downwards and the bottoms of the vertical sides, firstly facing vertically downwards, of