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There is growing concern about heavy metals pollution in peri-urban areas with the rapid development of urbanization in China.In this paper,heavy metal (Cu,Pb,Zn and Cd) balances on small-scale vegetable farming system were studied during the years between July,2003 and July,2005 in an industry-based peri-urban area (Wuxi) of the Yangtze River Delta Region of China.The objectives are to judge trend of the heavy metal accumulation in the agricultural eco-system and assess the healthy risk of heavy metals in soils and vegetables.Results showed that input via organic fertilizers contributed to major heavy metal inputs to the system in the study area which accounted for more than 88.5% of the total inflows of heavy metals.Inputs in the study area were quite high compared to yearly heavy metal inputs in European agricultural area,while the corresponding outputs were obviously low with just accounting for less than 10% of the total inputs.Consequently,Cu,Pb and Zn balances were positive in all plots.With reference to Chinese agricultural soil safety standard level 2,it might be seen that heavy metal contents in plots concerned were all lower than limits fixed in this standard,while soils in the study areas were higher than the background value of Anthrosols in Tai-hu Lake region.Also,assessment of healthy risk indicated that the leaf vegetables had a high risk in the study area.