Laminated shim stock, also known as peelable shims, is made of multi-layer sheet materials. Laminated shim stock is often used to adjust the assembly clearance and plays an important role in the aircraft manufacturing process. The existing manufacturing methods of the laminated shim stock is mainly mechanical milling and conventional blanking, both of which might have delamination phenomenon. In this research, the delamination on the sheared edge in the conventional blanking process of the laminated shim stock is studied. A conventional blanking finite element model of the laminated shim stock is established as well, the Cockroft-Latham damage model is used to analyze damage in the blanking process. It is found from the results of simulation and experiment that the various material behaviors of cross section is the main cause of delamination on the sheared edge.