Narrow stripe of InAs/InP quantum dot laser is fabricated by the chemical wet etching method.The materials of stripe are composed of InGaAs and InP in systems of InAs/InP quantum dot laser.A vertical stripe with width of 6 μm is achieved by choosing suitable rate of H2SO4∶H2O2∶H2O and H3PO4∶HCl and etching orientation of InP at room temperature.The laser emits its wavelength in the fiber optical communication region around 1.55 μm under continuous-wave mode.More than 12 mW output power from one facet is obtained at room temperature.