The key point of the stable operation of dry thin oil sealed gas holders is the sealing oil quality. The sealing oil deterioration reasons of dry thin oil sealed gas holders have been analyzed for the blast furnace gas holder and the coke oven gas holder, which are widely used in the iron and steel enterprises. And then the present sealing oil treatment technology is summarized. On this basis, the treatment technology of the sealing oil deterioration of dry thin oil sealed gas holders has been discussed according to the oil characteristics and the operating condition of the dry thin oil sealed gas holders in the iron and steel enterprises.