Nam Yoon-su is a model and actor under the agency "Agency Garten".

When he was a second -year school fashion model with Hallym Entertainment High School , he came to audition at five models agencies.[6] At this time, he signed a contract with Agency Garten and debuted as a CECI pictorial at the age of 17 in 2014 . Since then, he has been active as a model such as fashion magazines, fashion shows, lookbooks, and music videos.

Before his official debut as an actor, he had been acting through music videos, but began his acting career in earnest in 2018 .

In 2018, he appeared as Junha in the MBC every1 drama 《 4 Houses 》. This is Nam Yoon- soo's debut film as an actor . Jun-ha is a fashion photographer who studied abroad in France and is a friend of the female protagonist, Na-yoon . She returns to Korea and lives in a share house with Seonmin , Nayun , and Jihyeon . She acted like she liked Na-yoon, quietly taking care of her behind her back, with the image of her being like a romantic comic book heroine. There are a total of 7 episodes based on Naver TV , with only voice acting in part 1.[7] , will appear in earnest starting from Part 4.

In 2018, he appeared as Lee Gyeom in the 2018 Playlist web drama 《 If You Don't Do It, Do It 19 》. Lee Gyeom is a male friend who has a crush on the female protagonist, Kim Yuna (Shin Ki-hwan). He attracts the attention of many female students with his gentle smile, but he only has eyes for Kim Yoon-ah (Shin Ki-hwan) and silently takes care of her behind her back. However, Kim Yun-ah (Shin Ki-hwan) likes Kang Eun-gu (Jeong Ha-jun) and the two start dating, but in the end, her unrequited love does not come true. There are a total of 7 episodes, and Lee Gyeom's unrequited love episode is EP.03 .

In 2019, he appeared in the Dingo web drama “ I’m Not a Robot ” as Jeong Seong-yoon. Jeong Seong-yoon is an all-round fraud character who is good at grades, sports, and good looks. He also has a good personality and has many friends. She is the male friend of Mid Summer, and she has a crush on the female protagonist, Cha Eun .

In 2020, he appeared as Lee Chan-sol in the tvN D web drama “ Temperature of Language: Our Nineteen .” Lee Chan-sol is a high school senior preparing for the physical education department entrance exam and the male friend of the female protagonist, Woo Jin-ah .

In 2020, he appeared as Kwak Ki-tae in the Netflix original series “ Human Class ”. He is Seo Min-hee's boyfriend and is a second-year student at Gyewang High School. His image changed with his acting, which was completely opposite to his previous roles. For this work, he was nominated for the Best New Actor Award at the 57th Baeksang Arts Awards .

In November 2020, he appeared as Ha Kyung-hoon in the tvN drama Postpartum Care Center . Ha Kyung-hoon is a kind and personable delivery driver and is called Happy Man because of his charming smile.

In the JTBC drama " Monster , which aired in February -April 2021, he appeared as a police officer at the Manyang police box. In the fall of the same year, KBS 2TV drama " Yeonmo appeared as Lee Hyun -hyun.

In October 2024, he appeared as the main character Go Young in the TVING drama “ Love in the Big City ” for the first time since his debut.