The invention discloses a low-temperature denitration catalyst with strong anti-sulfur water-resistant properties and a preparation method thereof. Anatase type TiO2 is used as a carrier of the catalyst and is used for loading an active component, oxygen vanadium phosphate; the mole ratio of V to P in the active component, oxygen vanadium phosphate, is (1-6):1; the weight of the active component, oxygen vanadium phosphate, in the catalyst is 5%-15% of the total weight of the catalyst. According to the invention, the method comprises the following steps: with V2O5 as an active precursor, isobutyl alcohol as a reducing agent and benzyl alcohol as a solvent, performing reflux reaction at 150 DEG C, then adding phosphoric acid at proper ratio, and heating and refluxing; leaching, drying and calcinating the reaction mixture, thereby acquiring the active component, oxygen vanadium phosphate; lastly, adding the prepared active component, oxygen vanadium phosphate, and anatase type TiO2 with the specific surface area not below 250m<2>/g as the carrier into distilled water at proper ratio, stirring and mixing, and performing water bath drying and calcining, thereby acquiring the catalyst. The catalyst disclosed by the invention has higher low-temperature denitration activity and strong property for resisting against SO2 and water vapor toxifying.