Jang Han-Seo (In Han-Seo Jang) is a major character in the 2021 South-Korean dark comedy crime noir drama television series Vincenzo.

He is the young half-brother of Joon-Woo Jang who serves as the chairman of the latter's company Babel Pharmaceuticals Group after initially appearing to be the organization's leader.

At first he appeared to Hong Cha-young and Jang Jun-woo by meeting him, but he is not actually getting closes to her and believes that Jun-woo is not related