Despite mostly playing minor and supporting roles, he has gained popularity as a "scene stealer" in movies such as Introducing My Girlfriend, Ghosts Live, You Are My Destiny, Love, That Unbearable Lightness, Our Happy Time, Mudori, Dungfly, Bangjajeon, and Cheap Romance.

[2][3][4] He appeared in the 2010 film Unjust, directed by Ryoo Seung-wan, where he played a corrupt reporter who accepts entertainment and bribes from prosecutors and writes articles to suit his taste.

[7] In 2017, Oh became popular and gained critical praise for his portrayal of Min Cheon-sang, a lawyer on the brink of madness in the film Fabricated City.

[9] That year, Oh also appeared in the television series When the Camellia Blooms as Noh Gyu-tae and Hot Stove League as Kwon Kyung-min.

His portrayal earned him favorable reviews from the audience and the Baeksang Arts Award for Male Supporting Actor in the television category.