In Indonesia, cases of explosions due to gas cylinder leakage have begun to become the attention of the government and the development company. If a leakage happens when there are no people around it this can be dangerous because no one open the regulator on the LPG tube. To handle this, we design a system to detect leakage and release regulators if a gas leakage is detected. We build the automatic regulator system, we use several equipment including Arduino Nano, MQ-2 sensor and servo motor. The MQ-2 sensor is used as an input for gas leakage detection when the servo motor is used as a control output to open the regulator knob. Arduino Nano is used as a control device to read sensor signal input and control the output in the servo motor. Based on the results of the tests have been carried out the automatic regulator work well when a gas leakage happens by opening the regulator knob and the gas does not flow continuously. From the test results obtained an average response time to open the knop after the detected gas is 1,796 seconds.