The use case model is the simplest representation of a user's interaction with the system that shows the relationship between the user and the different use cases in which the user is involved. Use cases serve as a unifying thread throughout system development. Use-case model is the result of the requirements engineering, and it is used as an input to the later design and test phases. The aim of this thesis is to develop an Intelligent Computer Aided Software Engineering (I-CASE) tool that automatically extracts actions and actors of use case model from given functional requirements. The view we used to distinguish actor and use case in the research is to make use of what called thematic role. Based on that, we developed an algorithmic approach of manual practicing the developing of use case diagram, which is upgraded to a semi manual version that uses software for performing the revealing thematic roles by using semantic role labelling (SRL) software of NLP, and uses sketcher program to draw use case diagram by using yUML beta web service. The ultimate goal, which is called Intelligent Use Case Diagram Generator (IUCDG), utilizes Genetic Algorithm (GA), which is implemented by using C# programming language to develop a classification rule(s) to be used for recognizing each of use case and actor in addition to the SRL and yUML beta web service. The results are evaluated by using confusion matrix, which encompasses the calculating of number of factors, in which accuracy is one among them. The accuracy of IUCDG registers approximately >80 for recognizing actors and use cases. Keywords: Software Requirements Specifications, Thematic Role, Genetic Algorithm, Use Case diagram