To enable a parlor side to confirm an actual game condition from the open/close condition of an opening/closing means in a special game condition.

This managing device is to manage a game machine whose opening/closing means of a game device is opened/closed a number of times limited to prescribed maximum open/close times to bring a game into a first condition in which a game ball apt to win a premium and a special game condition in which the first condition is repeated from the starting by establishing a prescribed condition is generated. The numbers of opening/closing the open/ close means in the first condition are enabled to be accumulated and outputted.