The effects of temperature variation on D* of HgCdTe photoconductive detector are analyzed from signal and noise,and the expression of D* is deduced theoretically.Theoretical analysis shows that temperature change affects the concentration and lifetime of the carrier,which then has an influence on signal and noise,so D* can be improved in some degree by reducing the temperature of the detector.Through MATLAB simulation,the influence of changes of component and thickness on cutoff wavelength and peak wavelength of Hg1-xCdxTe photoconductive detector are analyzed.In order to get a higher detection response of HgCdTe photoconductive detector in the working waveband,the appropriate component x and thickness d should be selected when the detector operates in a certain temperature.