The utility model provides an outdoor box-type transformer station comprising a box body (50), a top cover (60) and a warning device, and the box body (50) is provided with a door. The warning device comprises a warning board (10) and connecting arms (20), the warning board (10) is arranged on the outer side of the door, the connecting arms comprise the first connecting arm (21) and the second connecting arm (22) connected with the first connecting arm (21), the second connecting arm (22) is rotatably arranged relative to the first connecting arm (21), the free end of the first connecting arm (21) is fixed on the top cover (60) or the box body (50), and the free end of the second connecting arm (22) is connected with the warning board (10). In the outdoor box-type transformer station, people unknown of current states can be prevented from entering the transformer station by the warning board when the door is opened, so that damage to the innocent people is prevented, and life security of the innocent people is ensured.