In order to satisfy the requirement of real-time tracing for photoelectric theodolite with multi imaging systems and to guarantee tracing precision and reliability,a new servo-control system according to Multiple Instruction Multiple Data Stream(MIMD) structure was proposed.The predictive filtering and data fusion of theodolite was derived theoretically.The results show that solution of data fusion needs a vast amount of numerical calculations.In order to satisfy the calculation requirement,a special parallel calculation system with three arithmetic units,two DSPs and a single FPGA was developed.The time outgoing of real-time calculation for each calculation unit was analysed.The simulation results show that the system can achieve 1.25 ms operation time in real-time for the theodolite with three imaging systems,while the CCD sampling frequency is 50 Hz and sampling frequency of photoelectric encoder is 800 Hz.