The invention discloses a fire identification method which comprises the following steps of: establishing a fire identifying mathematical model for identifying whether fire exists; collecting a smog concentration value in a detected area through a plurality of detectors; taking the collected smog concentration value as an input parameter value of the fire identifying mathematical model; obtaining a fire identifying result according to an output parameter value of the fire identifying mathematical model; and if the fire identifying result is the outbreak of fire, outputting an alarm signal. Besides, the invention also discloses a fire identification system. Different from the traditional threshold algorithm and trend algorithm, the fire identification method is characterized in that the fire can be identified according to the smog field distribution and the developing trend of the smog field distribution in the detected area through the established fire identifying mathematical model. The problems of ultrahigh false alarm rate, ultrahigh missing report rate, ultralow reliability and ultralow sensitivity are solved.