CECs of garden soils in Shanghai ranges between 10~20 cmol/kg and are significantly correlated with OM, pH, clay content, bulk density and soil aeration, so CEC is a good indicator of soil fertility, nutrient retention capacity and buffering capacity. It is, therefore, necessary to add CEC as an item to the index system for evaluation of urban garden soil quality and CEC of the gardens soils in shanghai should be controlled ≥14 cmol/kg. Key word CEC, City soil quality, Standard