This article analyzed the problems arising from retrofitting the 800 kt/a virgin diesel hydrofining unit into a 1.0 Mt/a OCT-M gasoline HDS unit at the refinery of Luoyang Petrochemical Company, and the optimized measures aimed at improvements in operation of HDS unit. The preliminary calibration results have indicated the high desulfurization rate and good selectivity of the HDS technology to fulfill the demand of Luoyang Petrochemical Company for product quality upgrading with the targets of technical revamp fully implemented.