The invention relates to a claus tail gas deep purification catalytic reduction oxidation process and a catalyst used by the claus tail gas deep purification catalytic reduction oxidation process and belongs to the field of claus tail gas purification treatment. According to the process, a low temperature reduction sulfur dioxide catalyst is adopted, H2S contained in the claus tail gas is used as a reduction medium, and SO2 contained in the claus tail gas is directly reduced and translated to sulphur; treated claus tail gas is subjected to oxygen replenishment, and the residual H2S in the tail gas is further translated to sulphur and sulfur dioxide under the action of a deep selection oxidation catalyst; purified tail gas is obtained simultaneously. The low temperature reduction sulfur dioxide catalyst is prepared from the following components by mass percent: 82-94% of anatase titanium dioxide, 4-16% of aluminium oxide and the balance of additives. By utilizing the claus tail gas deep purification catalytic reduction oxidation process, a catalytic reduction oxidation method is adopted, the yield of total sulfur of claus tail gas is high, system tail gas meets new national standards that SO2 content is less than or equal to 400mg/m<3> and H2S content is less than or equal to 5mg/m<3>, and the system tail gas can be directly discharged without an incinerator.