Park Se-young made her acting debut in a TV drama in 2002 when she was still a child, but left show business to concentrate on her studies.She returned to acting in 2011, and first drew attention after appearing in Jay Park’s “Know Your Name (Acoustic)” music video. Park then played supporting roles in family drama If Tomorrow Comes, revenge thriller Man from the Equator, melodrama Love Rain, period epic Faith, and teen drama School 2013.

In 2013, Park was cast in her first leading role in the daily drama Sincerity Moves Heaven (also known as A Tale of Two Sisters). She was also designated as one of the MCs on Music Bank.

Park appeared on the fourth season of We Got Married in 2014, a variety/reality show that paired celebrities into fake wedded couples (Park’s partner was Jang Wooyoung from boyband 2PM). Another leading role followed in weekend drama Glorious Day. Park then starred in two webtoon film adaptations – Fashion King (2014) and The Cat Funeral (2015).

After ending a contract dispute with S.A.L.T. Entertainment, Park signed with new agency Hunus Entertainment in 2015.[