Most of Chinese marine oil-water separators with large-size and low-efficiency, which adopted such techniques as filtering, gravity and centrifugal separation, especially with the separation method for polluted water having oil emulsion, were unable to meet the resolution IMO- MEPC.107(49) and the new environmental protection requirement by ISO Standard. Therefor, a small-sized, high-automatic marine separator suitable for oil-water was designed by innovation process and by integrated applications of combinational separation techniques of corrugated plate coalescence, porous medium and ultrafiltration membrane. At present, the equipment is put into batch production.