A positioning structure for a flexible cable having a movable portion is provided. In one embodiment, an FPC cable mounted to a base is received within a slit of a fixing plate. The FPC cable is disposed perpendicularly to a bottom surface of a base. On the fixing plate is provided a positioning reference which is spaced a predetermined distance from the bottom surface of the base. When the FPC cable is received into the slit, a part thereof is pushed against the bottom surface of the base to create an elastic force. An upper portion of a reinforcing plate affixed to the FPC cable for reinforcement comes into abutment against the positioning reference to establish a vertical position of the FPC cable.