The step-like InGaN quantum well (QW) and conventional InGaN QW for emission at a particular wavelength regime 415~425nm are designed and theoretically investigated,including the distribution of carriers’ concentration,radiative recombination rate,Shockley-Read-Hall (SRH) recombination rate as well as output performance and internal quantum efficiency.Theoretical research suggests that the step-like QW structure offers significant improvement of carriers’ concentration in the QW,especially hole concentration.Output performance and internal quantum well efficiency show 52.5% and 52.6% enhancement for step-like InGaN QW,respectively,in comparison to that of conventional InGaN QW.The improvement in luminescence intensity of step-like InGaN QW was found to be 1.54 times higher than that of the convention one.The reduction in SRH non-radiative recombination rate integral intensity can be the main reason the improvement of optical performance for step-like InGaN QW.