A product storage device includes: a product storage column storing products aligned in a row in a product storage path; a first gate moving back from and forward to a most downstream area that is downstream of a most downstream product in the product storage path; a second gate disposed in an upstream side with respect to the first gate and moving back from and forward to the most downstream area; a gate operation mechanism keeping the first and second gates in a state of having moved forward to the most downstream area in a standby state and to allow them to move back from the most downstream area when an operation command is given; and a measuring unit measuring the number of taken-out products by counting the number of changes in at least one of the first and second gates from a backward movement to a forward movement.