The invention discloses a unit half-hoisting and half-overside landing method of a ship unloader, which comprises the following steps: barge docking and floating crane hoisting, unit assembling of thefloating crane, unit assembling translation of the whole floating crane, a front girder of the ship unloader flatting, and towing of the ship unloader. The invention has the advantages that the well-debugged whole machine can be directly landed to a user dock and provides the production service for a user after being electrified and slightly debugged, a great deal of materials and manpower for final assembly on the spot are saved, the landing efficiency of the whole machine is improved, and the cost is saved.