This paper discusses the optical characteristics of a nonpolar a-plane InGaN/GaN quantum well (QW) with different indium compositions, QW well widths, and injection carrier densities. We find that the larger indium composition and smaller well width make the energy separation of |Yrang-like state to |Zrang-like state larger, and as a result enhance the polarization ratio of light. However, the polarization ratio decreases as the carrier injection increases, which might be a drawback for high power applications.