A new process-high-load activated sludge (HAS) process is reported for the treatment of municipal wastewater in medium and small cities. The marked characteristics of HAS process are no primary sedimentation basin, high-load, low resident time, good sludge-settlement ability, and no sludge swell. The removing methods of the organic pollutants are mainly of flocculation, adsorption and precipitation. The full-scale test results show that the average removal efficiency of the process is 68% for COD, 65% for BOD5, 86% for SS, 24% for TKN, 20% for TP. The effluent can meet "Standards for Irrigation Water Quality"（GB5084-92）. HAS process can reduce investment, operating cost and area.