It is not known when Qin Shubao was born, but it was known that he was from Qi Province (齊州, roughly modern Jinan, Shandong).

He became a soldier under the service of the major general Lai Hu'er (來護兒) during the reign of Emperor Yang of Sui.

The mission was considered dangerous, but Qin and another officer, Luo Shixin (羅士信), volunteered, and so Zhang gave them 1,000 men each and had them hide.

In 618, Emperor Yang was killed in a coup at Jiangdu (江都, in modern Yangzhou, Jiangsu), led by the general Yuwen Huaji.

Yuwen subsequently abandoned Jiangdu and advanced back north with the elite Xiaoguo Army (驍果), approaching Luoyang.

After a number of battles, Yuwen could not defeat Li Mi, and therefore left the area and crossed the Yellow River north.

Impressed, Emperor Gaozu sent a messenger to award Qin a golden bottle, stating to him: Qin then followed Li Shimin in defeating Liu's major general Song Jin'gang (宋金剛), contributing to Li Shimin's final victory over Liu later in 620.

Later that year, Li Shimin launched a major attack against Wang, who by this point had deposed Yang Tong and declared himself emperor of a new state of Zheng.

During the campaign, Li Shimin selected some 1,000 elite soldiers, clad in black uniform and black armor, commanded by Li Shimin himself, to serve as the forward advance corps, with Qin, Cheng Zhijie, Yuchi (who by this point had surrendered to Tang), and Zhai Zhangsun (翟長孫) as his assistants.

During initial engagement against Xia troops, Qin, Yuchi, and Li Shiji were able to defeat Xia forward troops, and Li Shimin subsequently wrote Dou, citing the battle as a reason why he should stop his campaign to aid Wang.

Qin Shubao is portrayed by Hong Kong actor Chan Wing Chun in TVB's 1987 series The Grand Canal (大運河)