To investigate the effects of direct continuous recycling of waste streams generated from drinking water treatment plant on effluent water quality, polite⁃scale experimental models was constructed and the changing rule of water quality was studied for 14 days both in summer and winter in the northeast China. The optimal recycle ratios of sedimentation sludge and filter backwash water were found to be 4% and 6% in summer, respectively, and was 2% and 6%in winter. Under the optimal recycle ratios, the continuous direct recycling waste streams could reduced the coagulant dosage by 33.3% in summer and 18.2% in winter compared to control trials based on reaching the sedimentation effluent standard (<2.5 NTU). Water quality parameters such as turbidity, color, UV254, TOC in settled and filtrated water were monitored periodically. Results indicated that contaminants could be removed more effectively in the recycling process compared to the control trials. Moreover, relative higher temperature could improve removal efficiencies. Over the entire operation period, there was no significant contaminants accumulation. Recycling waste steams was a feasible approach for enhancing coagulation process.%为考察连续回流净水厂生产废水对出水水质的影响，采用中试实验模型，研究东北地区夏冬两季连续回流净水厂生产废水14 d的水质变化规律．夏季沉淀池污泥和反冲洗水最佳回流比分别为4％和6％，冬季为2％和6％．在满足沉后水出水浊度达标（＜2．5 NTU）的前提下，夏、冬两季废水连续直接回流工艺与不回用相比，可分别节约33．3％和18．2％的混凝剂投加量．在整个回流运行周期中，连续监测浊度、色度、UV254、TOC等出水水质指标，结果表明，与不回流相比，回流工艺可以有效提高污染物的去除，而且，较高温度时还可以提高污染物的去除率．在连续回流过程中，出水水质稳定，未发现明显的污染物富集现象．废水回流是强化混凝过程的有效方法．
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