Computer game is a billion-dollar industry and is booming. Testing games has been recognized as a difficult task, which mainly relies on manual playing and scripting based testing. With the advances in technologies, computer games have become increasingly more interactive and complex, thus play-testing using human participants alone has become unfeasible. In recent days, play-testing of games via autonomous agents has shown great promise by accelerating and simplifying this process. Reinforcement Learning solutions have the potential of complementing current scripted and automated solutions by learning directly from playing the game without the need of human intervention. This paper presented an approach based on reinforcement learning for automated testing of 3D games. We make use of the notion of curiosity as a motivating factor to encourage an RL agent to explore its environment. The results from our exploratory study are promising and we have preliminary evidence that reinforcement learning can be adopted for automated testing of 3D games.