Abstract: Generating gear grinding is an important high-speed and high-precision gear processing technology. CNC gear grinding machine tool and workpiece synchronous control, namely electronic gear box control precision largely determines the precision of gear machining. In order to reduce the influence of grinding force changes, external disturbances and other factors on the synchronization control accuracy in actual working conditions, an adaptive synchronization control method of electronic gearbox is proposed to improve the anti-interference of the core control system of gear grinding. Firstly, a multi axis linkage model based on electronic gearbox is established; Then, an extended Kalman observer with adaptive function is studied to observe the grinding force generated in the multi axis machining process. The system processes the observation results, and designs feedforward based on the calculation results to compensate the deviation generated by the grinding force; Finally, compared with the observation effect of traditional observers in the simulation system, the simulation and experiment show that this method can effectively reduce the helix deviation and pitch deviation of gears, and ensure the anti-interference of the system.