The invention discloses a vehicle-mounted refrigerator. The vehicle-mounted refrigerator is arranged in the middle of a backrest of an automobile backseat and comprises a refrigerator body and a door body, a sliding rail is arranged on the refrigerator body, the door body is installed in the sliding rail in a sliding manner so as to control opening and closing of the refrigerator body in a sliding manner, and a concave structure is arranged in the sliding rail; and one or more of an automatic closing mechanism, an opening and locking mechanism, an opening and closing driving mechanism and a closing detection mechanism are arranged between the refrigerator body and the door body. The vehicle-mounted refrigerator is arranged in the middle of the backrest of the the automobile backseat and does not occupy the space in an automobile, the door body is installed in a sliding manner, the space in the automobile is not occupied when the door body is opened, and passengers on the rear seat can conveniently use the vehicle-mounted refrigerator. Meanwhile, the door body has at least one function of automatic closing, opening and locking, opening and closing driving and closing detection, the use experience can be effectively improved, and the practicability is high.