The invention provides an Nd2O3-ACF catalyst, a preparation method and an application in treating dimethyldisulfide (C2H6S2) odor waste gas. The preparation method of the catalyst comprises the following steps of: preparing impregnation liquid by using activated carbon fibers (ACF) as carriers, neodymium nitrate as a precursor and water as a solvent; loading neodymium into the activated carbon fibers (ACF) by adopting an initial wet method and an immersion method; and roasting to obtain the Nd2O3-ACF catalyst. The invention has simple treatment process, low treatment cost and obvious effect on removing the odor waste gas and particularly the dimethyldisulfide, and has the characteristics of easy reaction control, easy operation, convenient maintenance, and the like, thus the invention is an effective method for treating odor organic waste gas of sewage treatment plants (stations) and has quite wide market development prospect.