The invention, which relates to the technical field of vehicle braking performance detection, provides an apparatus for detecting a braking performance of a damaged vehicle. The apparatus comprises a loading rod, a braking force loader, a braking force sensor, a brake pedal force sensor installed at a pedal, a data acquisition card, and a computer. A flange connected with a wheel is arranged at one end of the loading rod and an adjusting block capable of adjusting a loading position is arranged at the other end. The braking force loader is arranged right below the adjusting block; and the braking force sensor is arranged between the braking force loader and the adjusting block. The braking force sensor and the brake pedal force sensor are respectively connected with the data acquisition card; and the data acquisition card is connected with the computer. With the apparatus, a braking performance of a vehicle that can not be driven due to damages caused by a traffic accident can be detected scientifically, accurately, and quantificationally. The provided apparatus has advantages of simple structure, small size, low cost, high portability, and good detection effect.