A method for model-based testing of an industrial system includes modeling functionality of an industrial system using a modeling computer language, enhancing the model by adding functionality or refining existing functionality, generating test suites from the system model, and executing the test suites. The modeling computer language is the Unified Modeling Language (UML), wherein modeling includes defining UML use case diagrams to describe relationships among use cases specified for the system and actors who interact with the system according to the use cases, defining UML activity diagrams to model process logic of each use case, wherein the activity diagrams comprise a sequence of activities and transitions, and defining UML class diagrams to specify data categories and attributes that are inputs to the activities of the activity diagrams, wherein data categories relevant for a use case are modeled as test variables in the activity diagram.