A security chip includes: a first medium layer; a second medium layer disposed on the first medium layer, where the first medium layer is an optically denser medium relative to the second medium layer, and a roughness of an upper surface of the first medium layer is greater than or equal to a preset threshold, so that light entering the second medium layer from the first medium layer is able to be totally reflected and/or scattered; and a semiconductor chip disposed on the second medium layer. Based on the above technical solution, light incident from a lower surface of the first medium layer is able to be totally reflected or scattered by the upper surface of the first medium layer, so that most of light cannot reach a logic or storage area on the front of the security chip, thereby achieving the purpose of resisting a laser attack.