GaSb-based InGaAsSb/AlGaAsSb type-I quantum-wells (QWs) laser diodes have been successfully fabricated. The wavelength is expanded to 2.6 μm with high output power. The device structures were grown by molecular beam epitaxy. Under the optimized QWs growth temperature of 500℃,the compressive strain of the QWs are defined to 1.3% for better optical quality. With a ridge width of 100μm and cavity length of 1.5 mm, the maximum output power of single facet without coating has reached up to 328 mW under continuous wave (CW) operation at room temperature and 700 mW under pulse condition. The threshold current density is 402 A/ cm2.