PURPOSE: To sufficiently secure the number of reservoired balls and to manifest the advantages of an island unit restoration replenishing system to a maximum.

CONSTITUTION: In a method in which a delivery device 1 is provided at an appropriate position at the terminal part or intermediate part of a pachinko (Japanese pinball game) island X in which plural pachinko boards 2 are provided in parallel, and an out ball from each pachinko board 2 is restored and supplied to each pachinko board 2 by delivering from the delivery device 1, a reservoir tank 20 in which a large number of pachinko balls are reservoired is provided on its upper side in the longitudinal direction of the island X by spreading over the plural pachinko boards 2, and the ball delivered from the delivery device 1 is supplied to the reservoir tank 20, and it is replenished from the reservoir tank 20 to each corresponding pachinko board 2.