A rotation balancing mechanism of an orbiting scroll of a scroll-type compressor that reduces the outer diameter of the compressor housing. A compression mechanism includes a fixed scroll and an orbiting scroll. The compression mechanism is coupled to a support frame at the front of a drive motor. A drive crankshaft is located between the drive shaft of the motor and a base plate of the orbiting scroll. The drive crankshaft causes the orbiting scroll to orbit. Follower crankshafts are located between the support frame and the base plate. The follower crankshafts permit the orbiting scroll to orbit and prevent the orbiting scroll from rotating about its own axis. A central balance weight is located on the drive crankshaft. The central balance weight opposes part of the centrifugal force that is applied to the drive crankshaft when the orbiting scroll orbits. Outer balance weights are attached to the follower crankshafts to oppose the remainder of the centrifugal force.