To provide a game board locking device which permits a game board to be smoothly stored in a game board storage concavity by paying no extra attention and the locking of the game board to be released by a simple operation of the game board locking device.

The game board locking device is made up of an underframe 2, a receiving frame member 4 journaled on the underframe 2, urged to separate from a game board attachment surface 50 by a first snapping means 15 and receiving the side edge of the game board 33, and a moving shaft 5 arranged on the underframe 2 and urged in one direction along the axis by a second snapping means 20. A notch 13 and a concavity 14 are provided in the receiving frame member 4 and an engagement groove 19 is provided in the moving shaft 5. When the moving shaft 5 is slid against the urging of the second snapping means 20, the receiving frame member 4 rotates, and the engagement groove 19 of the moving shaft 5 engages with the notch 13 of the receiving frame member 4. When the receiving frame member 4 is rotated against the urging of the first snapping means 15, the engagement groove 19 of the moving shaft 5 and the concavity 14 of the receiving frame member 4 agree, the moving shaft 5 slides along the axis, and the concavity 14 of the receiving frame member 4 engages with the moving shaft 5.