Abstract: Junction temperatures and spectral characteristics of InGaN+YAG white LEDs were measured at various driving currents and a constant environmental temperature, and the spectral curve under different junction temperatures was obtained, which indicated the dependence of InGaN+YAG white LEDs spectral characteristics on junction temperature. The experiment results show that the line width of blue spectrum is dependent on junction temperature, while the one of phosphor spectrum exhibits a weak dependence; the peak wavelengths of blue and phosphor spectrum have no dependence on junction temperature, while the peak intensity ratio of phosphor to blue spectrum has a good linearity.