A method of restoring a demulsification property of gas receiver sealing oil is disclosed. The demulsification property of the gas receiver sealing oil can be restored to a level of new oil through treatment, namely the oil water separating speed is less than 25 min, thus overcoming a practical problem that gas receivers are iced up in winter, and ensuring safe production. The cost-performance ratio is high. Acid values of oil products can be reduced, and an effect of restoring partial properties is achieved. The method at least prolongs the service lifetime of oil products by 50% or above, thus greatly reducing the operation cost of production.