The invention discloses a vehicle-mounted pavement crack detection system inspection device based on an eccentric adjustment mechanism, and aims to solve an inspection problem of a detection result ofa variable pavement inclination detection result of a vehicle-mounted pavement crack detection system. The vehicle-mounted pavement crack detection system inspection device based on the eccentric adjustment mechanism is mainly formed by a support seat (1), a connecting shaft (2), a pavement simulation plate (3), a connecting spring (4), an eccentric wheel (5), a rotary shaft (6), a motor (7) anda bottom plate (8). The system provides the vehicle-mounted pavement crack detection system inspection device based on the eccentric adjustment mechanism, which is small in occupied space, simple in structure, high in inspection accuracy, simple and convenient to operate, easy to install, lower in cost, and reliable in performance.