The high-performance InGaAsSb/GaAsSb/GaAs lasers emitting 1300 nm is simulated. Compared to the type-II quantum well GaAsSb/GaAs, In<sub>0.48</sub>Ga<sub>0.52</sub>As<sub>0.98</sub>Sb<sub>0.02</sub>/GaAs<sub>0.98</sub>Sb<sub>0.22</sub> has large bandoffset which will offer a better electron confinement. And GaAs<sub>0.98</sub>Sb<sub>0.22</sub> can reduce the effective strain of the highly lattice mismatched InGaAsSb quantum well. The transparent carrier densities of active unit is as low as 0.72×10<sup>18</sup> cm<sup>-3</sup>. The threshold current and slope efficiency of the InGaAsSb/GaAsSb/GaAs three quantum wells laser is equal to 83 mA and 0.62W/A. When the current is over 93 mA, external efficiency will reach 0.72. In order to further enhance the performance of InGaAsSb/GaAsSb quantum well (QW) laser, the asymmetric (0.5 μm/1.5 μm) waveguide structure is also studied.