System and method for underwater robot global positioning

PURPOSE: An underwater robot location measuring system and method are provided to measure the relative location information of a mother ship and an underwater robot based on the relative location information of the mother ship and a towing boat and the relative location information of the towing boat and the underwater robot. CONSTITUTION: An underwater robot location measuring system comprises a mother ship(100), a towing boat(200), and an underwater robot(300). The mother ship measures self-location through a DGPS(Differential Global Positioning System). The towing boat measures own location at the location separated with the mother boat. The towing boat obtains first relative information in regard to the mother ship by comparing location information of the mother ship and own location information. The underwater robot transfers distance information with the towing ship to the towing ship.