Go Soo first appeared in a soft drink TV advertisement wherein he waits for his girlfriend in a curfew and, in 1998, appeared as an extra in a music video, the band Position's "Last Promise". He made his first step onto television in 1999 through MBC sitcom Jump, where his handsome appearance and cute smile reminded the audience of Cho Hyeon Jae and Ji Sung. He also drew critical praise when he appeared in the drama series Piano in 2001. One review described him as an "actor with precision." Piano was his first drama series produced by SBS, where he was asked to sign a contract. After this, all of his dramas have been SBS-produced.
Go had his first movie hit in 2004 as a drug crime officer in Some, the first film in which he performed his own stunts. In 2005, he starred in action-packed TV series Green Rose, playing a simple man who fell in love with a rich woman and was accused of a crime he did not commit. Green Rose was shot in both China and South Korea, next to KBS television series Full House and Beijing My Love.
In 2005, Go was awarded the New Star Award at the 42nd Daejong Festival. His new project in late 2005 is a drama-comedy Marry A Millionaire, where he plays a delivery man who was asked by a TV producer to act like a rich man to attract several women by his handsome looks. After playing wholesome and simple roles in dramas and while Marry A Millionaire is playing, he appeared topless in a cellphone television advertisement. He is macho in his appearance as he takes care of his body by working out and playing sports. Go Soo started his military service on March 2, 2006 and he had been assigned as a Civil Service Personnel in Gang Nam District, Seoul. Go joined co-actor Ji Sung, Suh Ji Suk, and shortly, Song Seung-hun.
On April 25, 2008, he was discharged from the Military and he received recognition for being an outstanding Public Interest Service Personnel. After 2 years and 2 months of his military service, Go had resumed acting, this time in theater, with the project The Return of President Eom. He was invited to join upon the recommendation of his acting senior Cho Jae-hyun, whom he met while working on Piano. Cho had played as his character's father. According to a source close to Go Soo, "After acting in Piano, Cho Jae Hyun is the senior whom Go most respects." Go Soo was also one of the actors who appeared in the photoshoot "Kolon Christmas Photo Shoot" in 2008, along with co-actors Joo Jin Mo, Song Il-gook, Jang Geun-suk, and Park Jae-jung.
In 2009, he worked in a movie, White Night, based on a Japanese novel of the same title. Go also completed his very first photo diary, "24 Hours with Go Soo", which was produced by co-actor and singer Ryu Shi-won, who used him as a muse.It spans approximately 100 shots, which will be produced as a DVD. Ryu also supports Go's career.
He made comeback to television in a melodrama, under the production of his home network SBS, titled Will It Snow For Christmas? which began airing December 2, 2009. Go is also to star in the 2010 movie Psychic, which released in May 2010.
Go is now working on his upcoming movie, Highland Battle, which will be released summer of this year.