From the perspective of preserving the health of urban slow-flow water bodies, water quality dynamic monitoring of Dongfeng Canal located at Zhengdong New District, Zhengzhou City, had been conducted for 14 months in 3 years from 2011 to 2013. The results showed the canal were below Class to Ⅴ water quality in dry season. Some of the monitoring sections and part times even belonged to heavy pollution. The main pollution was organic matter with CODMn of 40~75 mg/L, maybe companied by ammonia nitrogen and total phosphorus beyond index. The slow-flow water showed organic pollution type, and likely turned into a combined pollution coexisted with eutrophication. Nowadays, the biggest issue that water quality recovery in the canal faced was water shortage. It was necessary to look for supplemental source with abundant water yield and preferable quality. The protective screen on water quality upgrade and functional rehabilitation were constructed through many measures including water yield security, bioremediation, ecosystem reestablishment, efficient administration and so forth.