He is best known for his role as Louis Huang in the ABC sitcom Fresh Off the Boat (2015–2020), for which he was nominated for the Critics' Choice Television Award for Best Actor in a Comedy Series in 2016.

Before these major roles, Park gained popularity by playing Steve, a prank replacement of Jim Halpert (dubbed "Asian Jim") in an episode of the NBC sitcom The Office, and starring in the recurring role of Governor Danny Chung in the HBO comedy series Veep.

[4] His mother was an accountant at the University of California, Los Angeles (UCLA) and his father owned a one-hour photo store.

"[4] He graduated with a bachelor's degree in English, with a concentration in creative writing,[14] and minor in Asian American studies from UCLA in 1997.

[8][15] He remained at UCLA, partly to continue acting with LCC, and later completed his master's degree in Asian American studies in 1999.

He cited Mike Birbiglia and Mitch Hedberg as early influences and would later perform alongside comedian Ali Wong.

[20] Park, Shin, Wong, and LCC co-founder Naoya Imanishi were also a part of the short lived improv group, "The Legendary Stage Ninjaz".

[24] Early in his career, when Park did not have a talent agent, he would book roles through diversity showcases at different television networks.

Park found work to be scarce in 2009 due to the Great Recession in the United States in 2008 and a potential SAG-AFTRA strike at the beginning of 2009,[27] so he began to focus on his own projects during this period.

Previously, he has appeared as Brandon in the comedy skit Too Fast (2010) and as the stepfather in the web series Home Is Where the Hans Are (2012).

[30][31] He created, directed, wrote, and starred in several short internet series for Channel 101, including Dr. Miracles, The Food, IKEA Heights and Dumb Professor.

[33][34] Park played the recurring character of Minnesota governor Danny Chung on the HBO comedy Veep.

For reference material on the role, he used Forest Whitaker's performance in The Last King of Scotland and the Vice documentary on North Korea.

[37] In 2015, he appeared as Jeff in the prequel 2015 series for Netflix, Wet Hot American Summer: First Day of Camp.

From 2015 to 2020, Park 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.

Park produced and starred in the Netflix original film Always Be My Maybe, directed by Fresh of the Boat creator Nahnatchka Khan, with Ali Wong.

[42] Park, Golamco and Hieu Ho launched the Asian American focused production company, Imminent Collision, and signed a first look deal with 20th Century Fox Television in October 2019.

[53] In 2019, Park rapped alongside Wayne Brady, Rafael Casal, Utkarsh Ambudkar & Daveed Diggs in "Housewarming Cypher".

"[54] Park has been featured in ads for HBO Go, Ally Financial, and the 2011 Father's Day Verizon Droid commercial.

[55][56] He plays a "doggie daycare owner" in a print and online campaign for Chase Bank, which aired in early 2015.

[64] Park is an active supporter of East West Players theater group in Little Tokyo, Los Angeles.