He hailed from Lanling 蘭陵 (modern Cangshan 蒼山, Shandong) and was made court gentleman retainer (congshi zhonglang 從事中郎) after being recommended by Minister of War (dasima 大司馬) Wang Yin 王音. He then rose to Grand Master of Remonstrance (jian dafu 諫大夫), then regional governor (mu 牧) of Jizhou 冀州 and then governor (taishou 太守) of the commandery of Yingchuan 穎川.
In 4 BCE Emperor Ai 漢哀帝 (r. 7-1 BCE) made him metropolitan magistrate (jingzhao yin 京兆尹), then Chamberlain for the imperial insignia (zhijinwu 執金吾). Wujiang Long was a honest person who freely remonstranted against the unjustified honour that the emperor's favourite Dong Xian 董賢 had received, as well as against the practice of office selling undertaken by Empress Dowager Fu 傅太后. Enraged, Emperor Ai demoted him to commander (duwei 都尉) of Peijun 沛郡. Wujiang Long was later pardoned and appointed governor of Nanjun 南郡.
When Wang Mang 王莽 (r. 8-23 CE) usurped the throne of the Han he took revenge for an old dispute with Wujiang Long and dismissed him.