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Aiming to study the long-term efficiency and performance of chemical oxygen demand (COD) and total nitrogen (TN) removal in riverbank filtration system under different hydraulic conditions, a long term simulated riverbank filtration system was built by using soil columns supplied with reclaimed water from Qinghe reclaimed wastewater treatment plant. The results showed that the system was effective in removing COD, the average removal rates of COD under continuous wetting condition and wetting/drying condition were 40.5% and 50.8%, respectively, over three-year period. COD removal primarily occurred at the upper part of the soil column (0~40cm), where there was high dissolved oxygen content and a large amount of microorganism. The removal performance of COD was improved in the wetting/drying column with relatively higher dissolved oxygen (DO) concentration under the unsaturated condition. And performance for the annual average COD removal kept stable under both conditions. The much higher removal rate of TN was obtained under the wetting/drying condition (80.7%) than that under the saturated condition (31.2%). Performance for TN removal under both conditions was increased gradually year by year. Temperature was one of the impact factors for TN removal in riverbank filtration system. The results showed that the removal rate of TN was increased exponentially under continuous wetting condition and increased logarithmically under wetting/drying condition with the temperature ranging from 15℃ to 31℃, respectively. The TN removal efficiency could reach higher than 90% as the temperature was higher than 30℃. The results can provide important information and basis for reclaimed water reuse for rivers and lakes.