The purpose of this thesis was to improve the quality of the corrugated board die-cutting tools. Die-cutting tool cuts corrugated sheet to a desired shape of the box. The thesis has been made in Stora Enso Packaging. Stora Enso Packaging produces corrugated cardboard further processing. A raw material of the corrugated sheet is a cardboard. The sheets are cutted in a rotary die cut machine according to the customer-engineered as a box or packaging. Each package has its own tool of choice. The cutting tool consists of plywood, rubber, as well as the cutting rules. The optimal shape of the tool is very important for the manufacture of the product. Stora Enso Packaging Heinolas rotary die-cutting machinery groups and the forwarding of the factory were interviewed to determine important measurements. The Final result of the thesis was improved quality and functionality of the die-cut tools.