The invention relates to a car handicapped-aided auxiliary chair device, comprising a car seat and a vehicle door, an end surface cam mechanism, a parking worm wheel and worm mechanism, a pedal mechanism, and a four-connecting rod mechanism; the end surface cam mechanism is arranged below the car seat; the worm and worm wheel mechanism is arranged at the external side of the left side of the car seat; one end of the four-connecting rod mechanism is movably connected with the lower left side of the car seat by a cylinder pair and the other end thereof is movably connected with the internal side of the vehicle door by a rotation pair; the pedal mechanism is arranged at the front side below the car seat. When the vehicle door is opened, the seat automatically rotates by 90 DEG and faces to the passenger; the height of the seat is lifted up synchronously, thus facilitating the passengers to be seated; when the vehicle door is closed, the seat is recovered automatically; when a handle which is arranged beside the seat is rotated, the pedal can turn over upwards and downwards. The device has smart and compact structure, reasonable technique and strong practicability, and provides humanized convenient services for the handicapped, the olds and ills who are about to get on the car.