Synthetic dyes are applied practically in all industries. World production of dyes increases every year, and their range is constantly expanding. Organic dyes are combustible, and their dusty-air mixtures represent a danger of fires and explosions. Consequently, in the development of measures to ensure fire safety is necessary to have information about the fire hazard properties of dyes. Currently one of the most urgent tasks is to develop universal prediction methods of physical and chemical properties of organic compounds. Promising important method is the descriptors method based on establishing of dependency the structure - properties. The purpose of this work - study the possibility of using the descriptor method for predicting the lower flammability limit (LFL) of anthraquinone dyes. The analysis found that the best correlation with the index LFL observed for geometric descriptors (gravitation index: all pairs and the molecule surface area) and the electrostatic descriptors (topographic electronic indexes: all pairs and all bonds). On the basis of these data approximation equation for calculating the LFL was obtained. Checking of the adequacy of the equation showed that the average relative error of estimate of LFL makes 30 %. Thus, the descriptors method can be used to assess the LEL of anthraquinone dyes.