A crane assembly for lifting marine vessels is provided. The assembly includes a sleeve having first and second clamps extending therefrom that are configured for engaging with a pylon of a dock and a boom pole slideably and rotatably received within the sleeve. A winch assembly is carried by the boom pole and including a winch and a cord. A crossbar is provided that has a main support that receives the cord and that has a pair of adjustable supports being carried along a length thereof that are adjustable to vary the space between the pair of adjustable supports. The adjustable supports are configured for engaging a support strap that is configured for passing beneath the marine vessel.