Nichkhun was born in Rancho Cucamonga, California to Thai-Chinese parents. Nichkhun has one older brother Nichan, and two younger sisters, Nichthima (Yanin) and Nachjaree (Chereen). At the age of five, he moved to Thailand with his family and studied at Dhepkanjana School and Tangpiroondham School. At the age of twelve, he studied at Wanganui Collegiate School in New Zealand for a year and a half and moved back to the United States to finish his schooling at Los Osos High School in Rancho Cucamonga, California. After high school, he was a coach at Rosemead High School for their badminton team. There, he was scouted by a scout manager of JYP Entertainment, at the Los Angeles Korean Music Festival.

After passing the audition hosted by JYP Entertainment, he signed a ten-year contract with the company but later re-signed for an eight-year contract, not including training, and was brought to South Korea in 2006 as a trainee, being put into a class of 24 other students. Park Jin-young informed him that he was required to learn how to sing and to dance, learn Korean and Mandarin Chinese, and to bulk up. He first appeared through MNET’s Hot Blood, a program that showed the intense physical training that 13 male trainees had to go through for the opportunity to debut in either a 4-member ballad group 2AM or a 6-member dance group (originally had 7 members until the leader Jay Park left the group) 2PM under JYP Entertainment.

After 2PM’s debut in 2008, Nichkhun began doing Thai endorsements, and was selected by the Tourism Authority of Thailand (TAT) for their campaign, “Come to Thailand; Let’s Take a Break!” Nichkhun has also done a wide variety of runway modeling including for Pony, and Andre Kim’s fashion show in 2008 with 2AM member Seulong.

Nichkhun played a main character in the 12-minute music video drama, released on February 8, 2010. Nichkhun also hosted JYP’s talent competition, Superstar Survival.

In December 2009, he had been confirmed to star in 2010 film “The Shining Diploma”, but due to scheduling conflicts with the filming delays, he dropped out of the project in March.

In May 2010, he was in a commercial for Everland’s Caribbean Bay water theme park along with 2PM Taecyeon & Chansung and Girls’ Generation members Yoona, Seohyun & Yuri.

On June 2010, it was announced Nichkhun was to be a cast member to We Got Married, pairing up with Victoria of f(x). Khuntoria was the couple’s name in We Got Married.

Nichkhun appeared in the music video of the single “Touch (觸動)” by Taiwanese Mandopop artist Wilber Pan, which premiered on January 31, 2011.In May 2011, 2PM Nichkhun was selected as the new 2011 models for Everland’s Caribbean Bay Aqualoop CF.

In July 2011, on “2PM Show”, he met the child actor Moon Mason, who had been called his lookalike since late 2009.

In 2013, he finished filming for One and A Half Summer in China and Greece. It is the first time that Nichkhun played the lead in the Chinese TV play. He used English and Chinese to finish filming. It will be on air on June,2014.Nichkhun is set to star in Japanese live-adaptation film Ouran High School Host Club as Lawrence, the president of a Singaporean corporation.

In 2012, Nichkhun starred in the debut Thai film Seven Something.