The DCB test for mode-I loading was utilized to obtain the interlaminar fracture toughness of two type of CFRP composites. Elastic theoretical and finite element analyses were conducted to model the R-curve behavior of laminated composites. In the theory, the bridging fibers were represented by elastic beams, while the stress field behind the crack-tip was calculated from the elastic foundation model. In the FE analysis the bridging fibers were modeled with TRUSS2D beam elements. The fracture toughness was evaluated numerically by the path independent J-integral. The analysis was done by the finite element code COSMOS/M 2.0. Experimental results were used from previous publications and comparison was made with the current computations. Comparison in the results shows, in the theory it is necessary to consider the fiber-bridging and the elastic foundation to obtain reasonably good, fully analytical values for the fracture energy. On the other hand, the FE models overpredict the mode-I toughness in the final stage of crack propagation. Simulating the bridging fibers these overpredictions can be eliminated.