The invention discloses a desoxidant with sulfur tolerance and a preparation method thereof. The desoxidant comprises a carrier and an active component, in terms of the total mass of the desoxidant, the carrier content is 10-20wt%, the active component includes an Fe oxide and an Mn oxide, wherein in terms of FeO, the content of the Fe oxide is 10-50wt%, and the content of the Mn oxide, in terms of MnO, is 10-50wt%, and the desoxidant also includes a modified molecular sieve, the content of which is 20-25wt%. The desoxidant with sulfur tolerance disclosed by the invention not only has high deoxidation precision and large oxygen capacity, but also has high hardness, and does not powder easily. At the same time, the desoxidant with sulfur tolerance has excellent desulfurization function.