Abstract: Aiming at the problem of excessive fire detection time delay, a new data source of fire detection is introduced. Fuzzy logic and D-S evidence theory are merged, and a signal fire detection method is proposed. This method uses CO concentration, smoke concentration, temperature, O₂ concentration, and heat release rate as fire detection data sources. It establishes a fire discrimination probability function to calculate the discrimination probability of no fire, smoldering fire, and open flame for each data source. The data sources are assigned weights using the Jousselme distance, and the multi-source discriminated information is fused through D-S evidence theory. The simulation results show that this method can detect fire 3-5 seconds earlier compared with the fire detection method that does not introduce O₂ concentration and heat release rate, thus improving the timeliness of fire detection.