“Emission standard of air pollutants for magnesia refractory industry”(DB21/3011-2018) is the first mandatory air pollutant emission standard in Liaoning province and the first mandatory emission standard in the industry.This paper introduces the background and basis of the standard preparation, and analyzes the standard execution time,emission limits and other relevant provisions,which is convenient for magnesium refractory enterprises,environmental protection enterprise and environmental authorities to  accurately grasp the main technical contents of the standard and actively promote the implementation of the standard.