A modified cyclic batch constructed wetland was innovated to examine the removal of organic matter and ammonia nitrogen from rural wastewater in the eastern area of China. The results demonstrated that mean percentage removal of BOD5 and NH‐N in the modified cyclic batch constructed wetland treating rural wastewater were 80 and 97%, respectively. Compared with conventional constructed wetland systems, the quality of effluent from the modified cyclic batch constructed wetland was higher when treating rural wastewater. The predominant process for BOD5 removal was aerobic biodegradation and biomass assimilation in the system, which accounted for more than 99% of total removal. Mass balance calculation of NH‐N showed that the average rate of nitrification was 6.247 g m−2 day−1, which was 7.5 times more than the amount removed by biomass assimilation. The supply of oxygen by the modified methods in the modified cyclic batch constructed wetland was significantly high for available oxygen, which was 76.984 g m−2 day−1, much higher than the demand for rural wastewater treatment. © 2009 American Institute of Chemical Engineers Environ Prog, 2010