The tensile-strained barrier GaAs/GaAsl.,PX quantum well (QW) structures fabricated on GaAs substrate have a remarkable potential for novel properties of laser structures. In the case of tensile-strained barrier GaAsIGaAsP QW, a small amount of light-hole (LH) and heavy-hole (HH) splitting is attainable within a large range of well width and P compositions. In order to shift the heavy hole and light hole energy levels, the concept of band-gap engineering is a useful tool to accept the particular devices operation. Basically, intermixing process is one of easy ways to achieve the modification of band structure. The effect of band structure on the intermixed GaAs QW with tensile-strained GaAsP barriers grown on GaAs substrates are reported.