In this paper, the optimal tracking performance of communication constrained systems by considering quantization, packet dropouts, noise and control input power constraints is studied. The frequency domain method is utilized to analyze the optimal tracking performance of the communication constrained systems. The explicit expression of the optimal tracking performance is deduced by partial fraction decomposition method and innerouter factorization method. The results indicate that the optimal tracking performance for a controlled object is only affected by the plant’s inherent characteristics (non-minimum phase zeros and unstable poles) and network factors (quantization, packet dropouts and noise). Eventually, a simulation is offered to validate the theory.