The invention provides a shield tunneling machine synchronous grouting mixing plant control system based on PLC control. The system comprises an operation control system, a PLC control system and an execution system, and is characterized in that the operation control system comprises an operation module, a communication module and a monitoring module; the execution system comprises a running module and a pre-alarm module; the operation module is provided with a remote operation platform and a local operation platform; the monitoring module is used for monitoring parameter changes in the mixing and grouting process; the pre-alarm module is connected with the running module, and when in the mixing process, the parameter changes exceed the preset threshold value, the pre-alarm module is driven to be started; according to the synchronous grouting mixing plant control system, the slurry proportion can be precisely adjusted according to different stratums, stratum sedimentation control is more effective, the influence of the shield tunneling construction on the surrounding can be reduced, automatic, intelligent and precise control over the burdening metering, mixing and discharging production complete process can be achieved, work efficiency and product quality can be greatly improved, and the obvious economic and social benefits are achieved.