A study of Single and Multiple Quantum Well material grown on GaAs by MBE was performed. We use GaAs/AlGaAs Superlattice Buffer Layer in the structure to bury the defects of the substrate. The quantum well material that obtained was used to made into quantum well lasers. In the room temperature, the lowest threshold current for 778nm lasers is 30mA, the liner output power is greater than 20 mW.