Provided is a battery attachment/detachment structure capable of maintaining favorable movement of a link mechanism and facilitating the attachment/detachment of a battery.　A lower end section of an operation lever (36) is pivotally supported by a first swinging shaft (36g) that functions as a leverage point on one end side of a link arm (72). A plug holder (70) is supported by a third swinging shaft (71) that functions as a leverage point on the other end side of the link arm (72). A hole part (100) through which the third swinging shaft (71) is inserted is formed in the plug holder (70). The plug holder (70) is configured so that the third swinging shaft (71) presses the inner peripheral surface of the hole part (100) accompanying the swinging motion of the link arm (72), and thus the plug holder moves in the pressing direction. The hole part (100) forms an idle traveling space in which the plug holder (70) does not move vertically even when the third swinging shaft (71) moves, and comprises a first shape section (101) that has a shape following an arc trajectory (R) of the third swinging shaft (71).