The invention discloses an automatic oiling machine for an automobile production line. In the machine, a cylinder body is fixed at one end of a connecting board, and a transmission wheel is arranged on the bottom of the other end of the connecting board; the eccentric position of the transmission wheel is hinged with one end of a connecting rod, while the other end of the connecting rod is hingedwith one end of a piston rod; a piston assembly is arranged on the other end of the piston rod and positioned in the inner cavity of the cylinder body; a drainage channel is reserved on the cylinder body, and the middle part of the draining channel is communicated with the inner cavity of the cylinder body through micropores; the upper port of the draining channel is provided with an oil pipe joint; the oil pipe joint is connected with an oil inlet pipe; a first one-way valve is arranged on a position, which is close to the oil pipe joint, in the draining channel; an oil nozzle is arranged onthe lower port of the draining channel; and a second one-way valve is arranged on a position, which is close to the oil nozzle, in the draining channel. The automatic oiling machine for the automobile production line does not need dynamic drive or manual operation, can realize automatically oiling rails along with operation of a conveying runner, and ensures excellent rail lubrication, and guarantees the smoothness and accuracy of conveying runner motion.