Abstract: A fixing device is provided for disposing an interface card in a casing of an electronic device, wherein the casing of electronic device includes lateral walls, a peripheral component bracket fixed to the casing. The fixing device includes a rotating bracket and an interface bracket, wherein the rotating bracket is fixed to the lateral wall, and connecting portions, and a first limiting portion. The interface bracket includes rotating portions pivotally connected to the connecting portions, a second limiting portion corresponding to the first limiting portion, and a coupling portion coupled to the peripheral component bracket. The interface bracket is rotated relatively to the casing of the electronic device, and the movement of the interface bracket is limited to the vertical movement by the rotating bracket.