To provide a roulette game device that allows a ball revolving on a roulette wheel to be easily observed from players and spectators surrounding the roulette game device, and can facilitate betting for a player.

An outer circumferential wall 29 of an inclined face 28, which is formed so as to extend from pockets 23 of a roulette device in an outer circumferential direction, includes a guide portion 291 that is provided at an upper portion thereof so as to protrude towards inside of the inclined face 28, in which a length that the guide portion 291 protrudes towards the inside of the inclined face 28 is shorter than a length of a radius r of the ball 11, which is thrown onto the roulette wheel.