Abstract: In order to further optimize the performance of semiconductor lasers,the band structure which influences many parameters of semiconductor lasers is discussed.Taking the InGaAs/GaAs strained quantum wells for an example,we obtain the conduction-band structures and the valence-band structures by using the finite difference method to solve the problem of 6×6 Luttinger-Kohn Hamiltonian which is considered the valence band mixing effect.The results show that the strain has changed the huge asymmetry between the light conduction band effective mass and the very heavy valence band effective mass in the traditional unstrained quantum well lasers.It is more conducive to improving the laser performance.