The invention relates to a polyarylsulfone amide fiber having a catalytic function and a preparation method thereof. The polyarylsulfone amide fiber is prepared with the polyarylsulfone amide fiber as a substrate with a catalyst being 0.1-10% in mass percentage being dispersed in micropores of the polyarylsulfone amide fiber. The invention also discloses the preparation method of the polyarylsulfone amide fiber. The preparation method includes steps of performing impregnation to a pre-stretched wire of the polyarylsulfone amide fiber in a catalyst precursor solution to obtain the pre-stretched wire containing a catalyst precursor; drying the pre-stretched wire; and performing high-temperature thermal stretching and thermal shaping, wherein the catalyst is generated during the high-temperature thermal stretching and thermal shaping process. In the method, preparation technologies of the fiber and the catalyst are integrated. The catalyst is composited among the micropores of the fiber so that the catalyst is not liable to fall off, a dispersing effect is good, a specific surface area is large, and a catalytic efficiency is high and the like. The polyarylsulfone amide fiber having the catalytic function can be widely applied in industrial high-temperature flue gas treatment, automobile tail-gas treatment and decomposition of organic substances in air or water.