Delamination in FRP composites causes a considerable reduction in the transverse load carrying capacity, which is a major apprehension to the aerospace and automotive industries. Because of comparatively low cost and the flexibility of measurement. Modal analysis based damage identification in the composite materials is usefully employed in structural health monitoring. Using normalized modal curvature the delamination location detection is discussed in this paper. For the intact and delaminated composite, numerical modal analysis is performed using ANSYS-ACP. Modal parameters (frequency and mode shape) are extracted from the simulated composite plate. Modal curvature at each node is calculated by double differentiation of mode shape deformation. Damage Index (DI) is formulated using the modal curvature of intact and delaminated composite plates. Analyzing DI at each node of the plate region delamination is identified. Damage Index based delamination identification validated with Image Processing technique. The proposed approaches successfully identify the delamination position and size of the composites.