Abstract: In order to understand how ecological ditches, same in depth (1. 30 m) and different in constructions (grass, fillers, grass and fillers), can reduce main agricultural non-point source (NPS) pollutants under the same condition, pollutants removal efficiency were evaluated under dynamic inflow concentrationρ (NH₄⁺-N)=0. 17-1. 23 mg·L^-1, ρ (TN)=0. 86-6. 13 mg·L^-1, ρ (TP)=0. 11-0. 24 mg·L^-1 and ρ (SS)=24. 0-70. 0 mg·L^-1. And the effects of practical application of ecological ditch were also analyzed. Results show that, all the three kind of ecological ditches were quite high in NPS pollutants removal efficiency (>50%), regardless of the difference in construction. Ditch with grass and fillers had the highest pollutant removal efficiency. The mean ammonia nitrogen (NH₄⁺-N), total nitrogen (TN), total phosphorus (TP) and suspended substance (SS) removal rates of the ditch were all higher than 70%, and with relatively high stability. The concentrations of TN and TP in the ditch were decreased exponentially along with distance. In simulated rainfall runoff experiment, the final TN removal effect of the actual 110 m ecological ditch was higher under the low inflow TN concentration, while TP removal effect was higher under the high inflow TP concentration. This research is expected to be of great practical guiding significance to the control of agricultural NPS pollution.