Abstract: In this paper, the composite laminates subjected to pure bendinq are modelled by using 3-D anisotropic finite elements and the distributions of stress and strain alongthe thickness are presented.The numerical results show that there is a stressconcentration near the bonding interface in the central region(far from tractionboundaries and free edges)of symmetric angle-ply laminates, which should be called“interlaminar effect”The abrupt change of the mechanical behavior of material onthe interfaces causes interlaminar stresses.The laminates are in 3-D stress state nearthe interfaces. The strain distribution of the 3-D numerical model is different from thestrain hypothesis of the classical laminate theory based on the Kirchhoff-Lovehypotheses of straight inextensional normals.