Based on evanescent field coupling, a channolod-substrate-planar-stripe(CSPS)GaAs/ (GaAl)As laser integrated with buried passive waveguide is designed by computer simulation/Phis integrated device contains two active parts coupled with a buried convex passive waveguide. The dependences of the model power transfer efficiency, the radiation confinement factor and the threshold current density on the normalized guide thickness, the central depth of the buried convex passive waveguide and the waveguide asymmetry factor are calculated, Using the effoctivc index mothod.tho channol width and the eftectivo chaimol width for which tho structure supports only the fundamental modo aro obtained for difforcnt waveguide structure parameters.