Thepolarization characteristics of TE, TM modes output from the 1. 3 μmInGaAsP/InP lasers with different ridge-waveguide width are measured. It is observed that there is the polarization competition between TE and TM modes in narrow ridge-waveguide laser. For wider ridge-waveguide laser,the polarization of the stimulated emission above threshold current exhibits only TE mode, there is no competition. The degree of polarization above and under threshold currents are calculated and discussed. The results show that it is possible to get stable polarization output if we choise strictly the parameters of the laser, control the evironmental temperature and rationaly use the devices, and it is not necessary to use any polarizer.