PURPOSE: To constitute the machine so that a player can execute a game operation in a posture corresponding to his choice by providing an operating member on a handy operating box formed separately from the game machine body.

CONSTITUTION: An operating box 6 has a necessary condition that a start button 3a and stop buttons 3b-3d of each reel 2 among various push-buttons, switches, pilot lamps, etc., provided on an operating part 3 are provided on a slanting face 6b of the box 6 whose side face is formed in a roughly triangular shape or a roughly trapezoidal shape. The push-buttons 3a-3d provided on this operating box 6 are provided on the slanting face 6b of the box body 6a. The slanting face 6b on which the push-buttons are provided are turned to the opposite side from the side of a player, but since they grow accustomed to the direction of a person's hand, they can be used easily. By extending a cord 7 from the box body 6a, providing a junction socket 7a and a plug 7b on a slot machine body 1 and the tip of the cord, respectively, and coupling the plug 7b of the cord 7 to the socket 7a of the machine side, a rotation of the reel can be started and stopped by the push-buttons 3a-3d of the operating body 6 side.