A fingerprint image enhancement method, comprising: receiving a fingerprint image; computing a horizontal variation image and a vertical variation image of the fingerprint image (300); computing a weighted image, wherein a weighted value of a first pixel corresponding to a finger ridge in the weighted image is greater than a weighted value of a second pixel corresponding to a finger valley (304); multiplying the horizontal variation image with the weighted image to generate a weighted horizontal variation image, and multiplying the vertical variation image with the weighted image to generate a weighted vertical variation image (306); computing a fingerprint orientation image according to the weighted horizontal variation image and the weighted vertical variation image (308); and performing fingerprint image enhancement on the fingerprint image according to the fingerprint orientation image (310).