Xi River (西江, pinyin: Xī Jiāng, Postal System Pinyin: Si Kiang, lit. "West River") is the western tributary of Pearl River in southern China. The other two main tributaries of Pearl River are Dongjiang River and Beijiang River. Many parts of Xijiang are navigable. It is the largest of the tributaries, being 2,197 km. Hsi River is another name it is called.
Another Xi is a minor tributary of the Jiulong River northwest of Xiamen.