Fire investigation is an important activity that investigates the cause and process of fire occurrence and develops prevention and response measures. However, it takes effort and time to conduct actual fire investigation and reproduction experiments and verification is difficult. Therefore, in this study, we intend to test the reliability of fire investigation results using a fire simulation program that simulates an actual fire. As a result of comparative analysis of domestic actual fire investigation results and fire simulation simulation results, the suitability of the fire investigation to the objective investigation results was evaluated and after a verification process, the reliability of the fire investigation could be confirmed in advance and a conclusion could be drawn, so the accuracy of the fire investigation played a major role in raising the Through this study, The accuracy and efficiency of fire investigations will be improved and provide useful guidelines and system improvement data to experts and government agencies related to fire prevention and policy.