To provide a keyboard for a personal digital assistant (PDA) that is attachable to a PDA in a front direction when in use, and is attachable in the opposite direction for back-folding or removable for storage when not in use and when only a PDA screen is used.

The keyboard, which is attached to a PDA set 9 when in use, includes: a hinge device 11 including a connector 16 for transmitting a keyboard input signal to the PDA, and an upper and a lower hinge cover 18 and 20; attaching/detaching means 13 positioned in the hinge device and attachable to the PDA in a front direction or the opposite direction; and a keyboard body part 23 connected to the hinge device so as to be folded and deployed thereon, and having a key part 22 on an upper face and an FPC keypad for inputting a key pressed on the key part in the interior.