Butyl-rubber is used as construction adhesives and it is mainly used in the form of sheets. The goal of the study is to design an extrusion die for the butyl-rubber sheet by using CAE. The role of the extrusion die for the butyl-rubber sheet is making flow uniform along the width direction of sheet. The extrusion die for the butyl-rubber sheet consists of manifold and land. The function of manifold is spreading the rubber from the entrance of extrusion die to the land area. And the function of land is making flow along the flow direction stable. Island and bumper are frequently used in the die design. Island reduces flow of center region and bumper is used for reservoir in the land region. Through this study manifold, land, island, and bumper for butyl-rubber sheet have been designed through computer simulation.