为寻求改善乡村微污染饮用水水质的有效方法，结合粗滤慢滤工艺研究的实践，阐述了该工艺氨氮的去除规律以及与溶解氧的关系，提出需氧量的估算方法。研究结果表明，粗滤慢滤工艺具有良好的去除ＮＨ３Ｎ能力，其效率主要受溶解氧的限制，实用工艺中，停留时间及水温对其影响不大。该工艺可直接应用于乡村饮用水的处理。 In order to seek an effective method to improve the quality of micro-polluted drinking water in rural areas, combined with the practice of coarse filtration and slow filtration process, the removal rule of ammonia nitrogen in the process and its relationship with dissolved oxygen are described, and the method for estimating oxygen demand is proposed. The results show that the coarse-filtration slow-filtration process has good ability to remove NH3N, and its efficiency is mainly limited by dissolved oxygen. In the practical process, the residence time and water temperature have little effect on it. The process can be directly applied to the treatment of rural drinking water.