Method: A cross - sectional study on the water quality of Tien, Hau rivers in June and November 2006 in some human communities living along river sides of three provinces: Đong Thap, Vinh Long and Can Tho. The water quality was assessed by Viet Nam Standard TCVN 5942 - 1995, the category A are applied to the surface water using for source of domestic water supply with appropriate treatments.