A full-size test rig of water-lubricated stern bearing (WSB) with an elevation adjustment device was built. High -precision wireless telemetry device obtained four film pressure signals. Six eddy current sensors were adopted to measure the axis orbit. The effect of bias load, rotational speed, and hull deformation on bearing lubrication characteristics are systematically studied. Experimental results showed the distribution lubrication characteristic of WSB at the axial direction. The WSB lubrication region can be divided into the three sub-regions in the middle and both ends of the bearing. Three lubrication sub-regions have different take-off speeds. Under the bias load, the negative pressure was found in the film pressure distribution. The hull deformation affects the position and area of each lubrication sub-region, changing the loads carried by the water film and asperity contact. Research results have a great contribution to WSB optimization structure design.