Aiming at the problem of lowprecision of multicylinder synchronous movement caused by unbalanced load of hydraulic jacking steel platform in super highrise building construction, a hydraulic synchronous control system was designed with industrial control computer as the upper computer and Siemens PLC as the lower computer. The key parameters of the system were tested and fed back by using highprecision displacement sensor and inclination sensor. Based on the classical PID control algorithm, the valve port opening of the symmetrical proportional valve was precisely controlled to regulate the flow into each cylinder, and then to meet the requirements of synchronous jacking of multihydraulic cylinders. The mathematical model of a single valve controlled asymmetric hydraulic cylinder was established, and the stability and system characteristics were analyzed. The results show that by using the PID control algorithm, the jackup formwork system has fast response speed, stable operation without overshoot and can meet the synchronization requirements of hydraulic cylinders.