1. An optical fingerprint recognition system, for recognizing a fingerprint pattern of a finger, comprising: a finger board, having a first plate face and a second plate face, wherein the first plate is opposite to the second plate face, the first plate face is used for being contacted by the finger thereon, and the second plate face has a plurality of micro-structures disposed thereon; an image capturing element, separated from the finger board for a distance and corresponding to the second plate face, wherein the image capturing element is used for capturing the fingerprint pattern of the finger; at least two light emitting elements, separated from the finger board for a distance and corresponding to the second plate face, the at least two light emitting elements disposed on two opposite sides of the image capturing element, wherein the at least two light emitting elements emit at least one light ray towards the finger board; an optical element, separated from the finger board for a distance and disposed between the finger board and the image capturing element, wherein the optical element has an opening opposite to the image capturing element, and the light ray reflected from the finger passes through the opening and enters the image capturing element; and at least two light guide elements, disposed on two opposite sides of the optical element respectively, wherein the finger board is disposed at one side edge of the two light guide elements, and the finger board, the optical element, and the light guide elements surround to form a cavity; wherein the micro-structures are used for guiding the light ray uniformly distributed in the finger board, such that the light ray is reflected to the image capturing element by the finger, and the image capturing element captures the light ray applied on the finger, so as to recognize the fingerprint pattern of the finger.