A hard drive connecting device for a notebook PC is installed in a case of the notebook PC for connecting a main board and a hard drive in the case, which includes a flexible board having at least a first side, at least a second side, and conductive lines for electrically connecting the first side to the second side; a first connector located in the hard drive bay electrically connected to the first side for electrically connecting the hard drive; and a second connector electrically connected to the second side for electrically connecting the main board. The flexible board facilitates electrical connection of the hard drive that allows reduction of both the size of the hard drive and the installation space required for the hard drive, thus facilitating profile miniaturization of notebook PCs.