A work machine, comprising: a telescopic boom; an actuator that extends and retracts the telescopic boom; a power source; an electric drive source that is provided in the actuator and drives using power supplied from the power source; an operating unit (45, 46) that operates based on power of the electric drive source; a first transmission shaft that rotates on the basis of the power of the electric drive source; a second transmission shaft connected to the operating unit (45, 46); and a joint that has a drive-side element fixed to the first transmission shaft and a driven-side element fixed to the second transmission shaft, the joint being able to take a transmission state in which both the drive-side element and the driven-side element rotate and a non-transmission state in which only either the drive-side element or the driven-side element rotates, the telescopic boom includes a first boom element (141, 142) and a second boom element (142, 143) that are telescopically overlapped with each other, and characterized in that the operating unit (45, 46) includes: a first connecting mechanism that connects the first boom element (141, 142) and the actuator based on an urging force of a first urging mechanism and releases the connection between the first boom element and the actuator based on the power of the electric drive source, and a second connecting mechanism that connects the first boom element and the second boom element based on an urging force of a second urging mechanism, and releases the connection between the first boom element (141, 142) and the second boom element (142, 143) on the basis of the power of the electric drive source. a telescopic boom; an actuator that extends and retracts the telescopic boom; a power source; an electric drive source that is provided in the actuator and drives using power supplied from the power source; an operating unit (45, 46) that operates based on power of the electric drive source; a first transmission shaft that rotates on the basis of the power of the electric drive source; a second transmission shaft connected to the operating unit (45, 46); and a joint that has a drive-side element fixed to the first transmission shaft and a driven-side element fixed to the second transmission shaft, the joint being able to take a transmission state in which both the drive-side element and the driven-side element rotate and a non-transmission state in which only either the drive-side element or the driven-side element rotates, the telescopic boom includes a first boom element (141, 142) and a second boom element (142, 143) that are telescopically overlapped with each other, and characterized in that the operating unit (45, 46) includes: a first connecting mechanism that connects the first boom element (141, 142) and the actuator based on an urging force of a first urging mechanism and releases the connection between the first boom element and the actuator based on the power of the electric drive source, and a second connecting mechanism that connects the first boom element and the second boom element based on an urging force of a second urging mechanism, and releases the connection between the first boom element (141, 142) and the second boom element (142, 143) on the basis of the power of the electric drive source. a first connecting mechanism that connects the first boom element (141, 142) and the actuator based on an urging force of a first urging mechanism and releases the connection between the first boom element and the actuator based on the power of the electric drive source, and a second connecting mechanism that connects the first boom element and the second boom element based on an urging force of a second urging mechanism, and releases the connection between the first boom element (141, 142) and the second boom element (142, 143) on the basis of the power of the electric drive source.