In the literature, interest in automatic control systems that do not require human intervention and perform at the desired level increases day by day. In this study, a Twin Delay Deep Deterministic Policy Gradient (TD3), a reinforcement learning algorithm, automatically controls a DC motor system. A reinforcement learning method is an approach that learns what should be done to reach the goal and observes the results that come out with the interaction of both itself and the environment. The proposed method aims to adjust the voltage value applied to the input of the DC motor in order to reach output with single input and single output structure to the desired speed.