Experiments were carried out at the Mitubisi Tank Nagasaki, to investigate the influences of blade shape upon the behavior of shallow-immersed screw propellers. Four model screw propellers of different blade shape were tested in open water with its shaft centre 1 diameter and 0.25 diameter of propeller below the surface.The results show that the drop of thrust and efficiency in shallow immersion is more serious for aerofoil type section blades with rounded leading edges than for usual ogival type section blades with sharp leading edges, and it is also for nallower tip blades than for broader tip blades.