Abstract: In order to investigate factors of the oxidation and self-heating of sulfide dust，and using the oxidation and self-heating temperature of sulfide dust and inner temperature when sulfur dioxide was produced as an indicator，and sulfur content，mine dust layer thickness and dust particle size of the sulfide dust as independent variables，the oxidation and self-heating initial temperature of sulfide dust and inner temperature when sulfur dioxide produced were gained by three factor and three level orthogonal tests.Gray system theory is used to calculate correlation coefficient of influencing factor to correlation degree of single objective function and multiple objective functions.And the average correlation degree of every influencing factor is calculated during transition from multiple targets into single target at correlation degree.Then，the condition for most easily occurring oxidation and self-heating of sulfide dust is obtained，which provides the basis for safe production of sulfur mine.

Key words: Sulfide ore dust, Orthogonal experiment, Gray system, Oxidative self-heating, Initial temperature