Yang Hui
It is not known when Yang Dongqian was born. His ancestors had been Tang officials, with his great-great-grandfather Yang Hui () serving as the governor of Suining Commandery (遂寧, in modern Suining, Sichuan) — and thus being datable to the reign of Emperor Xuanzong of Tang, during whose reign, for some time, Tang prefectures were known as commanderies (from 742 to 757). Yang Dongqian's great-grandfather (Yang Hui's son) Yang Mian () moved from there south of the Nanling Mountains, to Shixing, and made his home there. Neither Yang Dongqian's grandfather Yang Chui () and father Yang Zhen () were recorded to be in official service, but both were said to be honest and virtuous.