Ky-Mani Marley was born in Falmouth, Jamaica, to Anita Belnavis and reggae superstar Bob Marley. At the age of nine, Ky-Mani and his mother relocated to Miami, Florida. In his early youth, Ky-Mani was unaware of his musical abilities, sports being his first love. With his mother's direction, he received piano and guitar lessons and played trumpet in his high school band. As an athlete, he competed in soccer and American football.

While a teenager, Ky-Mani started rapping and deejaying. His first single was "Unnecessary Badness". He became inspired as a singer after being asked to sing a hook to a song during a recording session at a studio in Miami. Ky-Mani soon began experimenting with laying tracks, at times with his brothers, Stephen, Julian and Damian.

Marley signed to Shang Records where he recorded his debut album in 1996, Like Father Like Son, and several singles: "Judge Not" with Patra, followed by "Dear Dad," "Who The Cap Fit ", and "Sensimelia", all of which added to his growing reputation in the new generation of reggae musicians. In 1997, Ky-Mani joined forces with Pras of the Fugees, on "Avenue", a hit cover version of Eddy Grant's "Electric Avenue". Marley appeared at Midem when it was held in Miami. In the Cameo Theatre, Marley performed a set which was aired live by the Caribbean News Agency to 36 countries. He signed with Gee Street/V2 Records in 1997 where he completed a collaboration with label mate P.M. Dawn on the single "Gotta Be Movin' On Up". Marley's next recording was the 2000 release, The Journey. In 2001, he released his third studio album Many More Roads, which was nominated for a Grammy Award, and went on tour. In 2004 he released his fourth studio album, Milestone. In 2007, he released Radio. In 2015, he released another album, Maestro.

Ky-Mani Marley's acting work included lead roles in the Jamaican films, "Shottas" and "One Love." In 2018, Ky-Mani hosted his own festival called The Maestro Marley Cup. This event blends his love of soccer and music. The festival returned to Miami in 2021 and has plans to be an annual event. Kymani is currently working on his new movie, Vendetta, written and executive produced by himself. This project is expected to be released in late 2022. He is also working on a new upcoming album and is set to release a debut single from the project in Fall 2022.

Ky-Mani is passionate about his youth soccer program in Jamaica called Falmouth United.