Born in 25 October 1642, he was the eldest son of Koxinga (Zheng Chenggong) and a grandson of the pirate-merchant Zheng Zhilong. After the conquest of Fort Zeelandia in 1662 by his father, Zheng Jing controlled the military forces in Xiamen and Quemoy on his father's behalf. Upon the death of his father six months later, Zheng Jing contested throne as the King of Tungning with his uncle, Zheng Shixi. The dispute was resolved in Zheng Jing's favor after he successfully landed an army in Taiwan despite strong opposition by the forces of his uncle. This was followed by Zheng Shixi withdrawing his claim.