This article is based on Arduino, combined with LCD liquid crystal display, DHT11 temperature sensor, MQ-2 smoke sensor and DSM chip to design a home fire alarm. The smoke value and temperature value in the current environment of the fire alarm can be displayed in real time. Flammable in the environment When the gas concentration or temperature reaches the alarm value set by the alarm system, a light alarm signal and an audible alarm signal will be issued. The test results of the hardware welding circuit show that the circuit can achieve concentration display, temperature display, report alarm value setting, automatic alarm, and sound and light alarm to reach the design goal. Low design cost, small size, simple operation, suitable for promotion.