Kang Young-seok started out as a musical actor before making his screen debut in 2017 with a supporting role in tvN’s Revolutionary Love. This was followed by appearances in the SBS melodrama Should We Kiss First and in the tvN sageuk 100 Days My First in 2018. In 2020, he became part of the tvN series When My Love Blooms. He next played a detective in the 2021 JTBC drama Undercover. In 2022, he was cast in several TV series including tvN’s Military Prosecutor Doberman and JTBC’s Insider. In 2023, he joined the main cast of the second season of the tvN sageuk Poong, the Joseon Psychiatrist.

Kang Young-seok enrolled as a theater major at Chung-Ang University.