A thin fastening slice module includes a first fastening slice body and a second fastening slice body. The first fastening slice body includes a first surface, a first upper periphery and a first concave part. The first concave part is downwardly extended from the first upper periphery. The second fastening slice body includes a second surface, a second upper periphery and a second concave part. The second concave part is downwardly extended from the second upper periphery. The first surface has an area greater than the second surface. The first upper periphery is aligned with the second upper periphery. The second fastening slice body is connected to a front end of an image pickup device. The first fastening slice body is separated from the image pickup device. A recess structure is defined between the first fastening slice body, the second fastening slice body and said image pickup device.