In this paper,optical properties of the four kinds of 1 W white high-power LEDs are investigated under the driving current range of 100-900 mA.From the analysis,the internal reason for the phosphor conversion efficiency varying with the driving current mainly has two kinds:first,as the current increases,the quantum confined Stark effect causes a blue shift of the peak wavelength of the blue chips,resulting in reduced matching for blue light and phosphor;second,due to the current increasing leads to device temperature rising,the non-radiation of the phosphor is increasing and excited state energy level is splitting seriously,resulting in part of the energy decreasing,and the yellow wavelength presents red shift.By analyzing the combined effects of these two factors,the law of the phosphor conversion efficiency with the current changes is obtained,and the recommendations to improve the current characteristics of the white LED are made.