In this study, a constant temperature environment chamber with high stability is proposed. In the proposed design, the outer temperature is controlled by the air conditioner, the inner temperature is controlled by the electric current generated to control several thermoelectric cooling units. The separation design of the environment chamber from the cooling system can reduce the vibration caused by the thermoelectric cooling elements. This system adopted the Rake’s System Identification Method to obtain the system model, so that optimum PID parameters can be acquired from the simulation of Matlab Simulink. The results show that the vibration can be effectively reduced and the temperature can be controlled within the range of 20±0.007°C in the steady state.