The utility model relates to a sliding rack accompanying mechanism which comprises a longitudinal track, a sliding rack, an accompanying frame running track, an accompanying frame, telescopic frame running tracks, telescopic frames and connecting racks, wherein the longitudinal track is fixedly arranged; the sliding rack is connected on the longitudinal track by a lifting travelling wheel in a sliding way; the bottom end of the sliding rack is fixed with the accompanying frame running track; the accompanying frame is connected on the accompanying frame running track in a sliding way by an accompanying frame travelling wheel; the bottom end of the accompanying frame is fixed with the telescopic frame running tracks along the left and the right directions; the telescopic frames are connected on the telescopic frame running tracks in a sliding way by telescopic frame travelling wheels; the bottom ends of the telescopic frames are fixed with dial plate cylinders, the end parts of piston rods of which are fixedly provided with dial plates; and telescopic frames are also fixedly provided with the connecting racks, the end parts of which are provided with supporting blocks. The sliding rack accompanying mechanism effectively overcomes the defects that an aerial conveyer only can be arranged on a static conveyer on the ground, and a bodywork can not be accurately arranged on a support of the conveyer on the ground.