In 2015, he appeared as Jeff in the prequel 2015 series for Netflix, Wet Hot American Summer: First Day of Camp. He also appeared in Wong Fu Productions' first feature film, Everything Before Us. Park appeared with John Malkovich in the music video for Eminem's single "Phenomenal". He also appeared as a co-worker of Amy Schumer's character in Trainwreck. He also had roles in the films Southpaw (as Jed Wang) and The Night Before as Ethan's Boss.
Since February 2015, Park has starred as Louis Huang, patriarch of a Taiwanese American family, alongside Constance Wu, in ABC's television show Fresh Off The Boat (based on Eddie Huang's memoir, Fresh Off the Boat: A Memoir), written and produced by Nahnatchka Khan and executive produced by Jake Kasdan. He was the first actor cast on the show, with the producers having approached him before the pilot was ordered. Park initially felt uneasy about portraying a Taiwanese father as somebody of Korean heritage. However, Huang reassured Park that he was Huang's first choice to play his father. When they were staffing the writer's room, Park recommended Ali Wong for the position. The show ran for six seasons and was concluded on February 21, 2020.
Park has been featured in ads for HBO Go, Ally Financial, and the 2011 Father's Day Verizon Droid commercial. He plays a "doggie daycare owner" in a print and online campaign for Chase Bank, which aired in early 2015.
Park returned to UCLA as a keynote speaker for the Asian American Studies department commencement ceremony in 2015 and for English department commencement ceremony in 2017.