A magnetic fastener includes first and second lock bodies engaged with each other. The first lock body includes a first magnet and a fastener body. The first magnet is defined with a through hole extending through the two opposite end surfaces of the first magnet. The fastener body is movably received in the through hole. The fastener body includes a main body, an interface part disposed at one end of the main body, and a plurality of elastic arms extending outward from the other end of the main body. The interface part passes through the through hole. A receiving space is defined between the elastic arms. The inner side of the free end of the elastic arms is respectively provided with a clasp. The second lock body includes a second magnet and a hook body connected to the second magnet. The hook body is provided with a buckling part.