It is not known when Du Xiao was born. Both his grandfather Du Shenquan and father Du Rangneng served as chancellors during Tang Dynasty — Du Shenquen during the reign of Emperor Yizong, and Du Rangneng during the reigns of Emperor Yizong's sons Emperor Xizong and Emperor Zhaozong. Du Rangneng was a close confidant of Emperor Zhaozong's. In 893, after Emperor Zhaozong's failed campaign against the warlords Wang Xingyuthe military governor of Jingnan Circuit and Li Maozhen the military governor of Fengxiang Circuit — a campaign that Du Rangneng had coordinated after Emperor Zhaozong ordered him to even though he was against the campaign — Wang and Li marched on the imperial capitalChang'an; under duress from them, Emperor Zhaozong was forced to order Du Rangneng to commit suicide. After Du Rangneng's death, Du Xiao mourned him bitterly, and even after the traditional three-year mourning period, he still partially wore mourning clothes for over a decade and did not embark on an official career. His older brother Du Guang'ai was suffering from a mental illness, such that at times he would act out violently or speak angrily, but despite this, Du Xiao served him humbly as an older brother. During Emperor Zhaozong's Guanghua era, when the chancellor Cui Yin served also as the director of salt and iron monopolies, Cui offered him a number of positions in the imperial government — as an assistant to Cui as the director of the monopolies; as a Xiaoshulang, a copyeditor at the Palace Library; a county sheriff near Chang'an; and a scholar at Hongwen Pavilion ; he declined them all. Later, after Emperor Zhaozong was forced by the warlordZhu Quanzhong the military governor of Xuanwu Circuit to move to Luoyang, the chancellor Cui Yuan, who was then also serving as the director of taxation, offered him the posts of assistant to Cui as director of taxation and the deputy director of palace affairs. Cui spoke to him to persuade him to accept: Du Xiao therefore agreed to accept the posts. Shortly after, he was made Zuo Shiyi, an advisory official at the examination bureau, and soon was made an imperial scholar and Shanbu Yuanwailang, a low-level official at the ministry of rites. After Cui himself was removed by Zhu in 905, Du lost his position as imperial scholar and was only serving as Shanbu Yuanwailang. Several months later, however, he was given the responsibility of drafting imperial edicts, and was then given back his position as imperial scholar, and promoted to a supervisory position as Shanbu Langzhong.
During Later Liang
In 907, Zhu Quanzhong had Emperor Zhaozong's son and successor Emperor Ai yield the throne to him, ending Tang and starting a new Later Liang as its Emperor Taizu. Du Xiao was made Zhongshu Sheren, a mid-level official at the legislative bureau and continued to serve as an imperial scholar. In 909, he was made the deputy minister of public works and chief imperial scholar. That fall, he was made a chancellor with the designation Tong Zhongshu Menxia Pingzhangshi, as well as the deputy minister of census. In 912, Emperor Taizu was assassinated by his son Zhu Yougui the Prince of Ying, who took the throne himself. Zhu Yougui retained Du as a chancellor and gave him additional titles minister of rites and grand scholar at Jixian Hall. In 913, Emperor Taizu's nephew, the general Yuan Xiangxian, who was working in league with Emperor Taizu's son-in-law Zhao Yan and son Zhu Youzhen the Prince of Jun, rose against Zhu Yougui and attacked the palace. Zhu Yougui committed suicide. After Zhu Yougui's death, the imperial guards began to pillage Luoyang. During the confusion, Du Xiao was wounded by the soldiers and died from his injuries. After Zhu Youzhen subsequently took the throne, he gave Du posthumous honors.
