Fourth Nattawat Jirochtikul is a Thai actor and singer. He was nicknamed Fourth as he was born on King Rama IV's 200th birthday. After getting his start in the company's "Thailand School Star 2019" contest, Fourth signed with GMMTV. He graduated from Saint Gabriel's College by taking the grade twelve equivalency test and is currently a student at Chulalongkorn University's Faculty of Law.

Fourth started in the entertainment industry in 2019 when he became one of the two winners of the GMMTV's star search competition "Thailand School Star 2019". In 2021, Fourth made his acting debut in the series "F4 Thailand: Boys Over Flowers". In May 2024, for his work on "Moonlight Chicken", he won the Outstanding Rising Star award at the Komchadluek Awards.