GAME MACHINE SYSTEM

PROBLEM TO BE SOLVED: To make it difficult to fraudulently use an IC card and to conveniently perform lending of credits or the like, in a game machine system including a lending machine.SOLUTION: The game machine system 1 includes a slot machine 10 and a lending machine 20 for lending credits to the slot machine. In the IC card used in the lending machine 20, an intrinsic medium ID is recorded. A player can borrow the credit of the slot machine 10 from the balance of the IC card by inserting the IC card to the lending machine 20 and performing a lending operation. A card replacement monitoring means 208 of the lending machine 20 detects replacement to a different IC card, and when the prescribed three or more credits are left, the lending processing of the slot machine 10 is inhibited. When the credits are fewer than three, the fraction is cleared.