SLOT MACHINE

PROBLEM TO BE SOLVED: To provide a slot machine whose game development is so complicated to interest a player. SOLUTION: The machine is provided with four reels 3 displaying a lot of symbols 1 on their outer peripheral surfaces and arranged side by side with each other, a rotation driving means (c) rotation-driving the reels 3, a reel stop means provided with a reel stop button 7 stopping the reels 3 independent of each other, a display window 4 displaying totally twelve symbols 1 by displaying the symbols 1 at three places being the upper/middle/lower places of each reel 3 concerning each of the four reels 3, and a pay-out judging means (f) which selects respectively one symbol 1 concerning the three reels among the four reels 3 from the group of the symbols displayed in the window 4 at the time of stopping the reel and sets a line combining the selected three symbols 1 to be an effective line to judge prize-winning or not by the combination of the symbols 1 belonging to the effective line. The effective line has an effective line on the side of a left end including the symbols 1 of the reel 3a of a left end, the symbols 1 of the reels 3b and 3c and an effective line on the side of a right end including the symbols of a reel 3d of the right end and the symbols 1 of the reels 3c and 3b.