The utility model provides a BMW and MINI vehicle special 54-core test box assembly which comprises a box body with an inner cavity. The inner cavity of the box body is internally provided with a circuit board. A side wall of the box body is provided with a 54-core input interface and a 54-core output interface. The upper panel of the box body is provided with 54 groups of test sockets which are led by the circuit board. Each group of test sockets comprises an input socket and an output socket. The key point of the BMW and MINI vehicle special 54-core test box assembly is that a fuse piece is added between the input socket and the output socket and is positioned by using a bracket, and the bracket passes through the upper panel to be connected with the circuit board. The BMW and MINI vehicle special 54-core test box assembly has the advantages that the open-circuit test of each group of test circuits can be realized through the arrangement of the fuse piece, live wire short circuit and grounded wire short circuit can be carried out, a circuit exchange function can be tested, the test specifications of a control unit of less than 54 cores of BMW and MINI vehicles and a common vehicle electrical system are unified, and the open circuit, safe short circuit and safe exchange become possible.