He hailed from Liwu 蠡吾 (modern Boye 博野, Hebei) and later moved to Duling 杜陵 (near modern Xi'an 西安, Shaanxi). Wang Shang was a son of Wang Wu 王武 who had been made Marquis of Lechang 樂昌侯 (Marquis Gong 共侯) during the reign of Emperor Xuan 漢宣帝 (r. 74-49 BCE), and therefore soon became a secretary (sheren 舍人) of the Heir Apparent.
In 52 BCE he inherited from his father the title of Marquis and was appointed palace attendant of all government sections (zhucao shizhong 諸曹侍中) and Leader of the court gentlemen (zhonglangjiang 中郎將). During the reign of Emperor Yuan 漢元帝 (r. 49-33 BCE) he rose to the posts of General to the right (you jiangjun 右將軍) and Grand master of splendid happiness (guanglu dafu 光祿大夫).
Emperor Cheng highly esteemed him and appointed him Counsellor-in-chief (chengxiang 丞相) in 29 BCE. Minister of war (dasima 大司馬) Wang Feng 王鳳 envied Wang Shang's fast career and slandered him so that Wang Shang was dismissed in 25 BCE. He died shortly later, probably by suicide. His posthumous title is Marquis Li 戾侯.