The invention discloses a wiring method of optical fiber in a transformer. The wiring method comprises the steps that 1, the total wiring length of optical fiber is calculated; 2, a bracket is mountedon insulation paper of a transformer winding; 3, the optical fiber penetrates into the transformer and passes through the bracket, wherein the initial penetrating angle and the winding direction of awinding lead at the penetrating position of the optical fiber are same, along with the increment of the penetrating length of the optical fiber, the wiring angle of the optical fiber changes synchronously; 4, after the optical fiber penetrates into the transformer, multiple insulating adhesive tapes are attached between the optical fiber and the insulation paper, and the optical fiber is fixed preliminarily; 5, the winding tension of the optical fiber is adjusted so that the deviation ratio between the winding tension of each part of the optical fiber and the set standard value can be smallerthan or equal to 5%; 6, after adjustment of the winding tension is completed, the optical fiber is fixed by using an adhesive agent. The wiring method of the optical fiber in the transformer can overcome deficiencies of the prior art and improve the distribution evenness of the winding tension of the optical fiber in the transformer.