A mechanism for mounting a storage device such as a magnetic disk device to a terminal device, capable of simplifying the attachment/detachment of the storage device, requiring a smaller number of parts for the attachment/detachment and preventing external shock from reaching the storage device. Storage devices are mounted to a frame made of a flexible material such as resin which, in turn, is fastened to a terminal device, without screws, by inserting a portion of the frame into a hole on the terminal device. Means made of a flexible material are provided on the upper surface of the frame for fastening the storage devices for absorbing the external shock or vibration by the elasticity thereof.