Abstract: On the basis of the traditional system of horizontal subsurface flow constructed wetland (SSFW), a new system, namely, inserted ecological filter bed (IEF), was developed. Comparison was made between the two systems in pollutant removing effect in different seasons. Results show that IEF was higher than SSFW in pollutant removing rate and removed total nitrogen (TN), ammonia nitrogen (NH₃-N), total phosphorus (TP) and permanganate index (COD_Mn) by 63.6%, 78.4%, 64.7% and 51.9%, respectively, on average, during the entire experiment period, which was 13.1%, 6.9%, 12.1% and 7.3%, respectively, higher than what the latter did. Temperature was an important factor affecting pollutant removing rate of SSFW. The rate dropped significantly during the fourth season (Oct. to Dec.) of a year when temperature is low, while IEF still maintained a relative high pollutant removing efficiency in winter, removing TN, NH₃-N, TP and COD_Mn by 57.9%, 63.0%, 58.7% and 51.8%, respectively, which was 12.8%, 11.1%, 10.2% and 7.2%, higher than what SSFW did, respectively. All the findings in this experiment indicate that IEF can solve the problem of SSFW being low in pollutant removing efficiency in the low-temperature season, and has certain important significance in guiding purification of heavily polluted rivers.