The temperature dependence of threshold current density is calculated by taking the carrier losses(Auger recombination and non-Auger recombination)into account in strained quantum well lasers. The characteristic temperature and threshold current density are compared between tensile-strained quantum well laser and compressive-strained quantum well laser. There is a conversation temperature point(T₀)between Auger recombination and non-Auger recombination. When T is higher than T_c,Auger recombination is leading;T is lower than T_c,the non-Auger recombination is leading. There is a higher conversation temperature,a lower threshold current density and a higher characteristic temperature in tensile strained quantum well laser than in compressive-strained quantum well laser.