Backlight box structure of combined type vehicle-mounted display screen

The invention relates to the technical field of backlight box structures, in particular to a backlight box structure of a combined type vehicle-mounted display screen. The backlight box structure includes an inner box and an outer box which are assembled in a fastening mode, a plurality of heat dissipation muscles and bones are upward formed on the bottom surface of the inner box, and a heat dissipation ditch is formed between the adjacent heat dissipation muscles and bones; an upper through hole and a lower through hole communicate with and corresponding to the head and tail of the heat dissipation ditch are arranged on the top surface of the outer box, and a plurality of heat dissipation channels are formed among the lower through hole, the heat dissipation ditch and the upper through hole and the top surface of the outer box. According to the backlight box structure, the problems that the size of an existing display screen is gradually increasing, but heat dissipation performance ofa backlight box is poor,