Water quality, ground water especially is paid more and more attention by publics recently. What factors resulted in current ground water in the agricultural zone? more than 200 ground water samples were taken in the North China Plain at the lower reaches of the Yellow River. The results presented that about one quarter of total samples have higher nitrate concentration than that of drinking water standard. Even some heavy metals are over-standard. Human activity and nature resources control current water quality from long-term agricultural to coastal zone where were developed as potential arable farmland in the past ten years. These results will help the authorities to manage ground water and pay more attention to sources.