NOVELTY - Ultra deep desulfuration-octane number recovery of an inferior gasoline includes subjecting the inferior gasoline to modification treatment by reacting with two sections. The two-section reaction includes on a first reaction section, contacting the inferior gasoline to be treated to a first section catalyst with double functions for removing diene/selectively hydrogenating and desulfurizing to implement a hydrogenation reaction; and contacting reaction effusion of the first section to a second section catalyst comprising modified HZSM-5 zeolite in a second section of a reaction region.    USE - Method for ultra deep desulfuration-octane number recovery of an inferior gasoline (claimed).    ADVANTAGE - The method can achieve an excellent effect of hydrogenation modification of the inferior gasoline with middle and high sulfur and high olefin; can reduce losses of octane number; and maintains high liquid yield while greatly reducing olefin content and sulfur content.    DETAILED DESCRIPTION - Ultra deep desulfuration-octane number recovery of an inferior gasoline includes subjecting the inferior gasoline to modification treatment by reacting with two sections. The two-section reaction includes, on a first reaction section, contacting the inferior gasoline to be treated to a first section catalyst with double functions for removing diene/selectively hydrogenating and desulfurizing to implement a hydrogenation reaction; and contacting reaction effusion of the first section to a second section catalyst comprising modified HZSM-5 zeolite in a second section of a reaction region. The first section catalyst comprises, based on total quantity of the catalyst, molybdenum trioxide (MoO3) (10-18%), cobalt oxide (CoO) (2-6%), dipotassium oxide (K2O) (1-7%), phosphorus pentoxide (P2O5) (2-6%), and an aluminum-titanium-magnesium (Al-Ti-Mg) composite oxide carrier. The second section catalyst comprises, based on total quantity of the catalyst, MoO3 (4-8%), CoO (1-4%), P2O5 (1-3%), a modified HZSM-5 zeolite (50-70%), and an aluminum-titanium (Al-Ti) composite oxide binder. The modified HZSM-5 zeolite is a product obtained by subjecting HZSM-5 zeolite to hydrothermal treatment and to modification treatment of a mixed acidic solution comprising an inorganic acid and an organic acid.