Chang Tso-Lin (WG) (Chinese: 張作霖, pinyin: Zhāng Zuòlín) (1873 – June 4, 1928), nicknamed the "Old Marshall" or "Mukden Tiger", was a Chinese warlord in Manchuria in the early 20th century.

Of humble origins, he assisted the Japanese in the Russo-Japanese War (1904–1905) as leader of a Manchurian militia unit. He held various military posts under the Republic of China. From his appointment (1918) as inspector general of Manchuria until his death, he had effective control of Manchuria. He constantly warred to extend his rule southward from 1920 onward, contending in a three-way struggle with Wu P’ei-fu and Feng Yü-hsiang for control of the Beijing government. His Fengtien army occupied the Beijing-Tianjin area until driven out by the Northern Expedition (1926).

Chang was killed when the Japanese Kwantung Army bombed his train as he was returning to Shenyang having just handed over control of Beijing to the Kuomintang led by Chiang Kai-shek. The assassination was performed by a small group of military men commanded by the senior officer of the Kwantung Army, Colonel Daisaku Komoto. This was part of a plot to secure nearly all parts of Manchuria beyond the South Manchurian Railway Zone, which was ceded to Japan after the Russo-Japanese War. He was succeeded by his son Chang Hsüeh-liang for control of Manchuria.