The invention discloses a Fenton-containing sludge catalyst for water treatment, and a preparation method and an application method thereof, and belongs to the technical field of water treatment. Thecatalyst comprises a carrier and an active component, the carrier is prepared from clay, micalex, sepiolite, kaolin and quartzite as raw materials, the active component is prepared from Fenton sludgeas a precursor, the Fenton sludge is sludge dried at low temperature, the content of the iron element in the sludge is 60-70%, and the content of organic matters in the sludge is 10-15%; and silicatemineral carriers such as clay, micalex, sepiolite, kaolin and quartzite play a good skeleton supporting role, it is guaranteed that the catalyst has high strength, the substances are not likely to bedissolved in water, and the service life of the catalyst in water is guaranteed. The Fenton sludge contains the catalyst active component, and pores are generated in the roasting process of the catalyst, so that the porosity of the catalyst is ensured, and the contact probability of components in catalyst particles and ozone is increased; and the strength of the prepared catalyst is greater than 400 N, and the service life of the catalyst is prolonged by 2-3 years.