Preparation method of fiber photocatalyst

The invention discloses a preparation method of a fiber photocatalyst. The preparation method comprises steps as follows: 1), an organic solvent is uniformly mixed with absolute ethyl alcohol, and a mixed solvent is obtained, wherein the organic solvent accounts for 75%-85% of the total volume of the mixed solvent; 2), nano-titanium dioxide is added to the mixed solvent obtained in the step 1) to be uniformly dispersed, and a nano-titanium dioxide dispersed solution is obtained; 3), polyacrylonitrile fiber is pulled to pass through the nano-titanium dioxide dispersed solution and enter a coagulating bath to be cured and formed, and the fiber photocatalyst is obtained through washing and drying. The preparation method is simple in process and suitable for industrialization, and a prepared product has lasting and stable photocatalysis and is easy to recover after being used.