The invention provides a detachable middle channel structure and an automobile. The detachable middle channel structure comprises an upper cover plate, a rear vertical plate and two parallel side vertical plates. The bottom lateral sides of the rear vertical plate and the two side vertical plates are fixedly connected with a front floor. The rear ends of the two side vertical plates are correspondingly and fixedly connected with the two lateral sides of the rear vertical plate. The upper cover plate is arranged on the upper sides of the rear vertical plate and the two side vertical plates through bolt connecting structures. The detachable middle channel structure has the advantages of being simple in structure, stable, reliable, convenient to detach and assemble and good in sealing performance; the requirement for engine after-running oil injection of a gearbox external oil cooler can be met, convenience can be provided for check and maintenance of a gearbox and a transfer case, and sealing and protecting of an underbody of the automobile are easy.