The Ir(hpiq)_3is mixed into YAG phosphors with the weight concentrations of 0%,1%,2% and 3%,respectively.The influence of doping concentration and driving conditions on color rendering index (CRI) of the device is researched.Through testing CRI values o f LED before and after filling with silica gel and installing the light distribution lens,the influence of th e both on CRI is researched.The experimental results show that with the increase of concentration of Ir(hpiq)₃,the CRI of device also increases and the average CRI changes from 62.7to 85.7.The reason is that with the increase of concentration of red phosphorescent materials,the blue light that LED chips emit is absorbed more and the red components also increase,so the CRI is improved continuously.With the in crea se of the current,except that the CRI changing curve of the sample with the concentration of 2% is almost a straight line whic h is parallel to horizontal axis,the change of CRI of the remaining samples is obvious.The reason is the increase of red components and the decrease of optical radiation conversion efficiency.In this paper,the r eason that the CRI of the samples changes with the current before and after filling with silica gel and installing the light distribution lens is analyzed.