Dark current is one of the important factors that affect measurement accuracy of infrared detector, while the size and fluctuation of the dark current is mainly affected by the working temperature of the device.In order to meet the accuracy requirement of the temperature gradient and temperature control of device, we designed a high precision temperature control system by using two different control strategies including “limit slope” algorithm and incremental PID algorithm.Considering the operating characteristics of low voltage and large current of semiconductor cooler (TEC), we used a DC/DC convert to change the high voltage to low voltage, then used some transistors to control multi-channel TEC, in order to achieve the purpose of high conversion efficiency and get a “pure” output with low electrical noise.This temperature control system was applied to an InGaAs multi-channel detector.The result showed that:the detector temperature reached a stable state within specified time;and after entering the steady-state, temperature fluctuation ΔT is lessthan 0.02 ℃.The measurement accuracy of infrared detector can reach 0.2% as the temperature fluctuation ΔT is lessthan 0.2 ℃, so the design meets the requirement.