Abstract: The buckling of a circular dclaminate near the surface of a thick laminato is soudied in this paper.Thv thickness of the sublaminate is assumed to be small comparcd with the total laminate thickness.The transverse deflection including a bending-torsion and shear-extension coupling terms is suppcsed and the Rayleighgh-Ritz method is used for the analysis. Effects of the base laminate Poisson's ratio,radius of delaminate and layup on buckling strains are discussed.The results show that(1) the buckling strainse and ara indcpendent on the Poisson's ratio;(2)the buckling strains. increase when the the base laminate Poisson's ratio increases;(3)if there is tension buckling strain is determined by the Poisson's ratio only.