Composites are increasingly used in making structures strong and safe and for other purposes. Most composite laminates face damage from the environment since they are mostly located in the outer parts of structures. The strength of the structure is then degraded by stress concentration, dilamination or crack propagation, and so on. Strength degradation of laminates with holes or notches can be predicted by the point stress criterion or the average stress criterion of Whitney and Nuismer [1–3]. However, the fracture strength for locally surface-damaged laminates has not yet been predicted theoretically. Tsai and Wu [4] gave a strength criterion in terms of the scalar function for anisotropic materials. However, most laminates are symmetric, so that the equation for the fracture strength can be simplified by using the classical lamination theory. In this study, therefore, the equation for symmetric laminates is induced and verified by comparison with Lagace’s experimental results and Tsai’s prediction [5, 6]. Moreover, this equation is modified to predict the fracture strength for the surface-damaged laminates. To verify this modified equation, flawed specimens were fabricated, and the experimental results were compared with those from the equation. Fig. 1 is the load–strain curve for a uniaxially loaded laminate, showing multiple ply failures leading up to ultimate laminate failure. The total forces and moments at the kth knee in the curve are given by Equations 1–3 where N (n), M (n), e0(n), and κ (n) are the load, moment, strain, and curvature at the nth section and [A(n)], [B(n)], and [D(n)] denote the modified stiffness matrix [2]. { N