The 1.3-mu m semiconductor material systems are numerically studied with a LASTIP simulation program. The optimum active layer materials of AlGaInAs/InP and InGaNAs/GaAs system are suggested. For the AlGaInAs/InP system, we optimize the structure by varying the number of quantum wells, the linear GRINSCH, and the compensated tensile strain in barriers. The optimized active structure possesses four quantum wells, linear GRINSCH, and a compensated tensile strain in the barrier of 0.325% at an emission wavelength of 1.3 mu m. The characteristic temperature can be improved to 99.4K, 51.0K, and 68.6K as it is operating among 288K similar to 318K, 318K similar to 348K, and 288K similar to 348K respectively. Furthermore, the optimized structure can also enhance the stimulated recombination rate and reduce the Auger recombination rate because of the compensated tensile strain in barriers. The simulation results show that the active layer with a certain amount of compensated tensile strain in barriers is beneficial for improving the laser performance. On the other hand, the performance of the InGaNAs/GaAs lasers with quantum wells of different compressive strains is investigated. The wavelength of InGaNAs/GaAs system is about 1.3 mu m if the Ga composition in quantum wells is 0.54. The results of numerical simulation suggest that the stimulated recombination rate is larger and the Auger recombination rate is smaller when the Ga composition in quantum well is 0.50.