The utility model relates to a torque-controllable traffic accident vehicle braking force detection device. The device matches an asynchronous motor with an electromagnetic slip clutch to form a slip motor, and the slip motor is used to perform torque dynamic loading, thereby acquiring the braking torque of a traffic accident vehicle brake, and evaluating the braking performance of the traffic accident vehicle. The device comprises a detection device (A), a support device (B) and a guide device (C). The detection device (A) transfers torque generated by the slip motor to a force application chuck, and a PID controller is used to control the output of variable torque, thereby obtaining a braking force curve of the brake; the support device (B) is in rigid connection with the detection device through an upper support plate, and is matched with the guide device in a smooth manner through an upper guide rail; and the guide device (C) controls the detection device and the support device to move longitudinally through a linear guide rail. The torque-controllable traffic accident vehicle braking force detection device solves the problem that braking force of a traffic accident vehicle having no road test or bench test conditions cannot be detected, and the performance of an ABS system of the vehicle can be evaluated at the same time.