Wei Jiansu (韋見素) (687 – 25 December 762[1]), courtesy name Huiwei (會微), formally Duke Zhongzhen of Bin (豳忠貞公), was a Chinese politician who served as a chancellor during the reigns of Emperor Xuanzong of Tang and his son Emperor Suzong. As a young man, Wei served as a military aide to Emperor Xuanzong's father, the future Emperor Ruizong, then the Prince of Dan. He later served in various regional postings and senior offices at the Tang court in Chang'an, and though his conduct met with approbation, in the later stages of his career he was considered controllable. This, as well as his early connection to Emperor Ruizong, allowed the leading chancellor Yang Guozhong to install Wei as chancellor and director of the examination bureau late in Emperor Xuanzong's reign. During the chaos of the An Lushan Rebellion, Wei accompanied Emperor Xuanzong and Yang in their flight from Chang'an and was severely injured when the imperial guard massacred Yang and his family. Subsequently, after Emperor Suzong claimed imperial title and Emperor Xuanzong abdicated, Wei initially retained his chancellorship but was subsequently shifted to positions of less responsibility. He eventually left office altogether and died in retirement in December 762.