Software often controls the behavior of mechanical and electrical systems, as well as interactions among their components in cyber-physical systems (CPS), the risks in CPS systems could result in losing tools, features, performance, and even life. That is why software testing is important for validating it and preventing subsequent errors. For this purpose, various methods are used and the various tools represent the static as well as the dynamic behavior of an object-oriented software system. A state chart diagram is a well-known tool of UML which shows the dynamic behavior of states of an object-oriented system. The state transformation of an object is depending on the three major components like transition function, action, and possible inputs. The paths through which an object changes its state are determined by the state chart diagrams. These paths can be represented in the graphical form with the use of Finite State Machine (FSM). In this paper, a method has been developed for validating the UML state chart diagram through FSM by creating a Transition Table. To achieve this goal, a number of Test Cases have been generated to test the accuracy of UML State chart diagram by evaluating a real case study.