The need for home security alarm systems nowadays is a serious demand. As the number of fire accident are increasing every day, there has to be something that will keep us safe. We are all aware of the high end security systems present in the market but they are not easily available to everyone. We therefore intend to provide a solution by constructing a cost efficient electronic system that has the capability of sensing the gas. The project involves the use of Arduino, gas sensor, buzzer, GSM SIM900A, smartphone and a simple program. The sensor detect gas in its permissible range and triggers the alarm. It will also send the signal to Arduino and also to GSM SIM900A which processes the signal and set off the alarm along with detection message to the smartphone. With this system we can easily set up a security alarm in our home for unwanted accident.