"Ducal Son" Prince Zhang 公子章, personal name Ying Zhang 嬴章, was a minister in the state of Zhao 趙 during the Warring States period 戰國 (5th cent.-221 BCE).
He was the heir apparent of King Wuling 趙武靈王 (r. 326-299) and in 305 commanded the Central Army (zhongjun 中軍) during a campaign against the non-Chinese state of Zhongshan 中山. King Wuling later decided to name his beloved son Prince He 何 heir apparent. Shorly later King Wuling retired, and Prince He became king of Zhao. He is known as King Huiwen 趙惠文王 (r. 299-266).
Three years later Prince Zhang was given the title of Lord of Anyang 安陽君.
In 295, he rose in rebellion, killed counsellor Fei Yi 肥義, but was soon attacked and killed by Prince Cheng 公子成.