An optical fingerprint sensing device and an operation method thereof are provided. The optical fingerprint sensing device includes an optical fingerprint sensing circuit, an image superimposing circuit and a fingerprint matching circuit. The optical fingerprint sensing circuit is configured to capture an original image of the fingerprint. The image superimposing circuit is coupled to the optical fingerprint sensing circuit. The image superimposing circuit is configured to collect the original image of the fingerprint to obtain a plurality of original fingerprint images. The image superimposing circuit superimposes the original fingerprint images according to at least one superimposition parameter to obtain a superimposed fingerprint image. The fingerprint matching circuit is coupled to the image superimposing circuit to receive the superimposed fingerprint image. The fingerprint matching circuit performs fingerprint matching on the superimposed fingerprint image.