The Kanmon sea area is a marine traffic congested area and a rich fishing ground in Japanese coastal sea area. Authors have investigated opinions of 94 fishermen, 29 pilots, 388 navigational watch keepers of the domestic vessel regarding reduction of conflict between fishing boats and vessels in this area through a questionnaire. This study has been analyzed each opinion of fishermen, pilots and watch keepers of domestic vessel. And these objective analyses revealed any difference of opinions between fishermen, pilots and watch keepers of domestic vessel. In these analyses, about 80% of fishermen have opinion about cooperative avoiding vessels. However, any fishermen have admitted minimum distance between fishing boat and vessel less than limitation of minimum distance between fishing boat and vessel that about 80% of pilots and watch keepers of domestic vessel have been aware. And, about 50% of watch keepers of domestic vessel have expected to reduction of conflict between fishing boats and vessels when fishermen operate AIS and VHF radio equipment. But then, over 60% of pilots have negative opinion about reduction of conflict between fishing boats and vessels when fishermen operate AIS and VHF radio equipment.
