The present invention relates to an automatic control system of a water washing and neutralization process in a gelatin production process. The system comprises a neutralization tank and a PLC control unit; a liquidometer is arranged at the inner wall of the neutralization tank, an aerator pipe, a phosphate pipe, a hydrogen peroxide pipe, an inlet pipe are disposed at the upper portion of the neutralization tank, and a drain pipe and a water recovery pipe are arranged at the lower portion of the neutralization tank; an aeration disc pipe connected with the aerator pipe is arranged in the neutralization; a flowmeter is installed on the inlet pipe; the PLC control unit includes a mainframe, an extension frame and an industrial control computer; the mainframe includes a power supply, a programmable controller, an interface module IM365I, a simulation module and an input module; the extension frame includes an interface module IM365II and an output module, and the interface module IM365I is connected with the interface module IM365II; the liquidometer and the flowmeter are connected with the simulation module; the input module is connected with a phosphate valve, a hydrogen peroxide valve, an inlet valve, a drain valve and the signal feedback end of the water recovery valve; and the output module is connected with an aeration solenoid valve, the phosphate valve, the hydrogen peroxide valve, the inlet valve, the drain valve and the signal output end of the water recovery valve. According to the invention, the production cycle may be shortened.