Lee made his acting debut in 2011, and first gained recognition from playing a rebellious student in the teen drama School 2013. Thereafter, he played supporting roles in television dramas such as My Love from the Star (2013) and Descendants of the Sun (2016). Lee gained popularity following his comedic role in Confession Couple, and was cast in his first major role in Welcome to Waikiki (2018). 2018 was professionally successful for Lee, as he also played the lead actor in the critically well-received "Children of Nobody".
Lee has also appeared in both independent and commercial films, notably Leesong Hee-il's White Night (2012) and Kim Ki-duk's One on One (2014). In 2018, he stars in two films - drama film Monsters (also known as Wretches) which tackles teenage bullying; and omnibus horror film Pension: Dangerous Encounter.