He hailed from Duling 杜陵 (near modern Xi'an 西安, Shaanxi) and was, although coming from a poor family, a well-educated persons who was acquainted with vice Censor-in-chief (yushi zhongcheng 御史中丞) Chen Xian 陳咸. When Wang Feng 王鳳 took over regency for the young Emperor Cheng 漢成帝 (r. 33-7 BCE), he undertook an empire-wide selection of worthies avaible for official appointment.
Zhu Bo was made magistrate (ling 令) of Liyang 櫟陽 and soon rose to the post of regional inspector (cishi 刺史) of Jizhou 冀州, then Bingzhou 幷州. He then was appointed governor (taishou 太守) of the commandery of Langya 琅琊 and then transferred to the post of Chamberlain for the national treasury (dasinong 大司農).
Because of a minor offense in office he was demoted to governor of Jianwei 犍為 in the far southwest, where he was able to pacify the rebellious native tribes of the Southern Man 南蠻. He was rewarded with the post of governor of Shanyang 山陽 but soon withdrew because of illness.
Cured again, Zhu Bo was appointed Grand master of Splendid Happiness (guanglu dafu 光祿大夫), then Chamberlain for law enforcement (tingwei 廷尉) and general (jiangjun 將軍). Zhu Bo was again dismissed when his friend Liu Li 劉立 was accused of some crime.
Emperor Ai 漢哀帝 (r. 7-1 BCE) brought him back to the office of Grand master of splendid happiness and then made him metropolitan magistrate (jingzhao yin 京兆尹). His carreer lead him further up to the office of Grand Minister of Works (dasikong 大司空), and then Censor-in-chief (yushi dafu 御史大夫). Zhu Bo was then involved in an intrigue of Empress Dowager Fu 傅太后 and her nephew Fu Yan 傅晏, Marquis of Kongxiang 孔鄉侯, and managed to drive out of office Counsellor-in-chief (chengxiang 丞相) Kong Guang 孔光 and Grand Minister of Works Shi Dan 師丹.
Zhu himself succeeded Kong Guang and was concurrently given the title of Marquis of Yangxiang 陽鄉侯. When the intrigue was reveiled, Zhu Bo committed suicide.