Based on ¹³⁷Cs technique, a quantitative model for soil erosion has been established, and the amountof soil erosion and nutrients losses have been calculated.The resul ts showed that the average amountof soil erosion of various profiles in forestis 1313.6 t/(km²·a), and the erosion in vegetable land is much hig her, so there is soil erosion in hilly region of Taihu Basin.The main factors affecting soil erosion are vegetable cover and cultivation, and the sortorder of soil erosion amounton different landforms from high to lowis as follows:vegetable land >middle slopping hill with masonpine >middle slopping upland with bamboo >top land.The nutrients loss is correlative with soil erosion, and the average loss for organic matter, total nitrogen, total phosphorus and total potassium in forestis 28.29, 1.38, 0.35 and 16.76 t/(km²·a), respectively.Therefore, it's time to pay attention to soil erosion in this area, and take some measures toreduce its effecton soil fertilizer and water quality in Taihu Basin.