A crane comprising a multistage telescopic extendable/contractible boom having a base end boom, a jib connected to the boom, and a jib overhanging storage mechanism for overhanging/storing the jib with respect to the boom: the jib overhanging storage mechanism comprising: a guide roller that is provided at one of the jib and the base end boom; a guide that is provided at the other one of the jib and the base end boom, and guides the guide roller; a jib fixing pin that is provided at one of the jib and the base end boom; and a pin socket that is provided at the other one of the jib and the base end boom, and has an insertion hole into (48,49) which the jib fixing pin can be inserted, wherein the guide is configured such that the jib is pulled toward a bottom surface of the base end boom, and subsequently the jib moves along the base end boom, by the guide roller being guided with contraction of the boom; the jib fixing pin and the insertion hole (48,49) are disposed such that when the jib moves along the base end boom with contraction of the boom, the jib fixing pin is inserted into the insertion hole (48,49); the jib fixing pin has a distal end portion formed in a conical shape; characterized in that the pin socket has a front end rib and a rear end rib; a front end insertion hole configuring a front end opening portion of the insertion hole (48, 49) is formed in the front end rib of the pin socket; a rear end insertion hole configuring a rear end opening portion of the insertion hole (48, 49) is formed in the rear end rib of the pin socket; the front end opening portion is a vertical hole along a vertical direction of a cross section of the boom, the vertical direction being a direction toward a top surface from the bottom surface of the boom in a state where the jib is pulled toward the bottom surface of the base end boom; the rear end opening portion is a round hole; an inside dimension of the front end opening portion of the insertion hole is larger than an outside dimension of the jib fixing pin; and an inside dimension of the rear end opening portion is substantially the same as the outside dimension of the jib fixing pin. a guide roller that is provided at one of the jib and the base end boom; a guide that is provided at the other one of the jib and the base end boom, and guides the guide roller; a jib fixing pin that is provided at one of the jib and the base end boom; and a pin socket that is provided at the other one of the jib and the base end boom, and has an insertion hole into (48,49) which the jib fixing pin can be inserted, wherein the guide is configured such that the jib is pulled toward a bottom surface of the base end boom, and subsequently the jib moves along the base end boom, by the guide roller being guided with contraction of the boom; the jib fixing pin and the insertion hole (48,49) are disposed such that when the jib moves along the base end boom with contraction of the boom, the jib fixing pin is inserted into the insertion hole (48,49); the jib fixing pin has a distal end portion formed in a conical shape; characterized in that the pin socket has a front end rib and a rear end rib; a front end insertion hole configuring a front end opening portion of the insertion hole (48, 49) is formed in the front end rib of the pin socket; a rear end insertion hole configuring a rear end opening portion of the insertion hole (48, 49) is formed in the rear end rib of the pin socket; the front end opening portion is a vertical hole along a vertical direction of a cross section of the boom, the vertical direction being a direction toward a top surface from the bottom surface of the boom in a state where the jib is pulled toward the bottom surface of the base end boom; the rear end opening portion is a round hole; an inside dimension of the front end opening portion of the insertion hole is larger than an outside dimension of the jib fixing pin; and an inside dimension of the rear end opening portion is substantially the same as the outside dimension of the jib fixing pin.