The investigate results of the phosphate-banning in detergents in Taihu region show that 98% of the shops in the whole Taihu catchment sale phosphate-free detergents and 99% of the people use phosphate-free detergents at the end of 1999. So the measure of banning phosphate in detergents is very effective and about 1353. 81t/a of phosphorus 14.07% of the total phosphorus loading of Taihu Lake is cut off. These are advantages of controlling eutrophication in Taihu Lake. Otherwise these are still some problems taken into account such as the quality and cost of phosphate-free detergents.