Software testing is an essential part of the software development life cycle. It aims to create a highly uncompromising framework. It is used also to determine whether or not the provided outcomes match the anticipated results and confirms that the system is error-free to produce more precise, trustworthy results. Automated testing based on UML is one of the testing approaches and has become the de facto standard for software modeling. Models are specified to represent the relevant, desirable features of the System Under Consideration (SUC). These models are used as a basis for automatically generating test cases to be applied to the SUC. Although, model-based testing that conducted on early phase of software development process show higher efficiency, it still has some issues, time consuming and effort consuming. The reason of these issues is that the existing model-based testing approaches are based on models that lack of semantics and don’t take into consideration the specificity of the used design patterns. This project will target these gaps by taking into consideration the semantic described in the used software patterns in the development process. It proposes an approach where automated testing will be enriched by the description of the design pattern knowledge and then the proper test cases will be generated based on this knowledge. This also will help to reduce the efforts in the automated model-based testing.