An electronic-component holding apparatus and an electronic-component mounting system each of which assures that a nozzle head holding a plurality of suction nozzles is easily attached to, and detached from, a head holding member, are provided. A suction surface of a head holding member is held in close contact with a to-be-sucked surface of a revolver head so as to define a head-related negative-pressure chamber that holds the revolver head by utilizing suction. The revolver head is revolved, and moved upward and downward, with the head holding member.