Yi River may refer to:

• Yí River, river in Uruguay, tributary of Río Negro
• Yishui River (宜水 or 宜水河), a right-bank tributary of the middle Xiang River
• Yi River (Henan) (伊河), China
• Yi River (Hebei) (易水), China, flowing through Yi County, Hebei
• Yi River (Shandong) (沂河), China, flowing through Linyi

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