A counterweight loading and unloading device and a movable crane have a freestanding pallet (10) with two ends whose upper end faces are used for holding a counterweight (61). The two ends of the freestanding pallet (10) are both equipped with a cavity, and at least one telescopic oil cylinder (11, 12, 13, and 14) is provided in the cavity. A fixed end of the telescopic oil cylinder is fixed with the freestanding pallet (10), and a telescopic end of the telescopic oil cylinder is coupled with a pallet lifting mechanism for lifting the freestanding pallet. The device is not limited by a planar space of a vehicle frame and a turntable height of the movable crane. An integral dimension of the movable crane is not increased, thus preventing integral dimension of the movable crane from exceeding a road traveling standard. The structure of the device is more compact, and the telescopic oil cylinder plays a role of the counterweight, thus enabling stress of the turntable to be more reasonable.