ABSTRACT: Problem statement: Building UML diagrams is a very important and time consuming task for both requirements and design phases. However, some of these diagrams, such as use-case and class diagrams can be considered as a transition between the two phases. Approach: Through this study, the event table will be used to derive the use-case and class diagrams. Results: A new CASE tool to automate the proposed approach will be introduced, that is, the UML diagrams generator (UMLdg). Conclusion: It is clearly noted that the proposed CASE tool (UMLdg) gives an ideal and reasonable methodology to construct the intended use-case and class diagrams from any comprehensive event table. Furthermore, this tool will save the time for the building process of such diagrams.