The invention discloses a base mechanism of a vehicle seat carrying machine. The base mechanism comprises a T-shaped front supporting base plate, front supporting wheels are installed on two symmetrical portions of the front supporting base plate respectively, an asymmetric portion of the front supporting base plate is horizontally arranged, and a triangular supporting frame is arranged at the upper rear of the tail end of the asymmetric portion and provided with a front support and two rear supports. The front support is fixedly connected with the tail end of the asymmetric portion of the front supporting base plate, the rear supports are symmetrically arranged along the axis of the asymmetric portion of the front supporting base plate, and rear supporting wheels are installed at the bottom ends of the supports respectively. The front supporting base plate and the triangular supporting frame form a fixed base. The two front supporting wheels and the two rear supporting wheels provide four-point horizontal supporting. The front of the base mechanism is in a low and flat supporting plate shape, and the low and flat design enables the seat carrying machine to extend forwards to the bottom of a vehicle, so that a seat is sent into the vehicle. On the other hand, the front protraction of the front supporting base plate is long, forward overturning torque generated during upper carrying of the seat can be offset, and good stability is provided.