The invention provides a PLC (Programmable Logic Controller) automatic control device for neurosurgery drainage. The PLC automatic control device comprises a drainage tube, a flow monitor, a guide pipe, a regulating valve, a wire A, a power distribution cabinet, a collection bag, a discharge pipe, a skull pressure monitor, a wire B and a heart rate monitor; the drainage tube is arranged above the flow monitor; the regulating valve is arranged below the flow monitor by the guide pipe, and forms an electric appliance circuit with the power distribution cabinet by a wire; the regulating valve is arranged above the collection bag; the discharge pipe is arranged below the collection bag; the skull pressure monitor forms an electric appliance circuit with the power distribution cabinet by the wire B; the heart rate monitor forms an electric appliance circuit with the power distribution cabinet by a wire. By arranging a PLC, drainage can be performed timely, drain is prevented from exosmosis to infect a wound, the drainage speed is controlled flexibly, the work intensity of medical workers is reduced, and the surgery quality is ensured.