Abstract: With the rapid development of China's economy, modern information technology is developing faster and faster. At present, modern information technology has been applied to all walks of life and has achieved good results. The introduction of information technology into the fire accident investigation work can accurately find the cause of the fire, which not only improves efficiency, but also effectively prevents similar fire accidents. The scientific application of modern technology to the investigation of fire accidents, promotion of the information development of fire investigation technology, and improvement of the accuracy of fire investigation are important aspects of current research. Based on this, this article analyzes the necessity of applying modern information technology in fire investigation, and proposes the application countermeasures of modern information technology in fire accident investigation.