Gas spillage prompts different mishaps bringing about both material misfortune and human wounds. The danger of blast, terminating, suffocation depend on their actual properties such poisonousness, combustibility, and so forth The quantity of passings because of blast of gas chambers has number of passings has been expanded lately. To dodge this issue there is a requirement for a framework to distinguish the spillage of LPG. Gas spill recognition is the way toward distinguishing conceivably unsafe gas spills by methods for different sensors . A few plans of LPG discovery and ready framework have been proposed in the writing. Apeh et al. planned kitchen gas spillage discovery and programmed gas shut off framework . T.Soundaryaet al. introduced the chamber LPG gas. In this our research paper, we have proposed a LPG/CNG GAS LEAKAGE DETECTION BASED ON IOT. AS we know that because of more demand and use of LPG, our proposed system would be very helpful to monitor the usage of LPG on a daily basis and to alert us about any hazards and big damages that may happened due to LPG leakage. We have made a framework that advise the client of the measure of LPG left so that suitable measures can be taken. As we probably are aware LPG is an exceptionally unsafe and inflammable gas,and the framework we have made it additionally used to caution the client with their disturbing capacity when there is spillage of LPG so that actions are taken to dodge a blast. LPG leakage is detect by our system with the help of gas sensor via SMS. When the concentration of LPG in air increase to a certain level,then after the gas leakage system of the controller is detected and measured by the leakage detector in which many of the electrical devices are like LED, buzzer and microcontroller are fixed. And the notification is delivered to the user, notify through an SMS to the verified mobile number.