The main pollutants of the runoff from urban residential area are organic pollutants and suspended solids. The biodegradable ability of organic pollutants is low. The style of coagulants, the best reacting condition, the quantities of medicament and micro-sands are confirmed by the experiment of the strengthened coagulation and sedimentation with micro-sands. The experiment shows that the effect and velocity of the coagulation and sedimentation with micro-sand materials can be increased and the removal rate of turbidity is 99.7% , the removal rate of COD is 92.6%. The two main indexes turbidity 1.66NTU,COD 35mg/L are superior than the quality standard of the miscellaneously using water. So the coagulation and sedimentation with micro-size materials is a simple, convenient and effective method of the treatment utilization and pollution control of the runoff from urban residential area.