It is necessary to set directions and measures to manage the question of water pollution arising from the illegal discharging of sewage and inappropriate management. Therefore, the main purpose of this thesis is to measure the water quality improvement value which means the willingness to pay(WTP) measured by using contingent valuation method(CVM) as one of direct valuation measurement methods and to maintain the environmental facilities in the public sector utilizing WTP which reflects the economic value of civil desire on the persistent improvement of water quality.
It was found clearly that the more income a household earns, the more consciousness they have about the water quality in the Han river and the higher educaton level a household has and the closer they live from the Han river, people are more strongly willing to pay to improve the water quality of the Han river.
If the water quality in the Han river improves up to the level which allows all kinds of entertainments including swimming, promenade, yachting, etc., the aggregate annual amount of willingness to pay to improve the water quality in the Han river is estimated to be approximately 2,860 billion won. And then, it may contribute to enhance the water quality in the Han river.