This paper designs an indoor fire information alarm system based on multi-sensor. It mainly uses multi-sensor and single-chip computer as the core components of the indoor fire information alarm system. It cooperates with other devices to realize the functions of real-time indoor temperature detection, automatic fire alarm, prompting fire extinguishing and so on. The main devices include IAP15F2K61S2 MCU, MQ-2 smoke sensor, DS18B20 digital temperature sensor, flame infrared sensor, LCD12864 liquid crystal display and GSM module. The design has simple structure, stable performance, convenient use, low price and intelligent fire information alarm, which has a certain practical value.