To solve the problem of more time required for the operation of the bets to meet the requirement of depressing the single bet button many times for a larger number of the bets in the conventional slot machines, in which the setting of the number of bets is limited by the number thereof previously allotted to each bet button.

Touching on the perimeter of a number of bets display part 32 actuates the display of the ten numeric keys 30 to validate the input operation of the numerals with the ten numeric keys. After the inputting of the numerals with the ten numeric keys 30, touching the perimeter of the number of beds display part 32 again makes the display of the ten numeric keys 30 disappear and the number of bets is recognized by the main CPU 42. Upon the recognition of the number of bets, the amount of money given by the multiplying of the unit amount of money equivalent to a single bet by the number of bets is set by the main CPU 42 for the gambling. Thereafter, when a handle 9 or a spin switch 13 is operated by the player, the rotary processing with the reels 2 to 4 is carried out, thereby starting the slot machine game.