Sidney Royel Selby III was born on May 3, 1997, in the Bedford–Stuyvesant neighborhood of Brooklyn, New York. He began practicing vocals in the school choir and at church. After getting shot at the age of 14, he began to embark on a music career and dropped out of high school.
Desiigner embarked on his rapping career under his original moniker Dezolo. He later began working on his tracks under the alias of Designer Royel, as Royel is his middle name. It was his sister who convinced him to drop the middle name and add the extra I. Under his new pseudonym, Desiigner released his official debut track, produced by The Shell God and titled "Zombie Walk", on December 3, 2015.On December 15, 2015, his commercial debut single, titled "Panda", was released on YouTube and SoundCloud, and on iTunes just five days later before being re-released in February 2016.
On February 11, 2016, Desiigner signed a recording contract to GOOD Music, under the aegis of Def Jam Recordings. After signing a record deal, Desiigner was subsequently featured on the two tracks, "Pt. 2" (which features an interpolation of "Panda") and "Freestyle 4" performed by Kanye West. These two tracks were included on West's seventh album The Life of Pablo. Desiigner later performed his newest song, "Pluto", at the 2016's South by Southwest (SXSW) music festival. In an interview with Billboard, Desiigner confirmed the release of his upcoming trap mixtape, titled Trap History Month.
On May 5, 2016, American record producer Mike Dean, announced that he would be executive producing Desiigner's debut studio album. On May 24, 2016, Desiigner announced the title of his debut album to be The Life of Desiigner.In June, XXL magazine revealed their annual "Freshmen Class" for 2016, which included Desiigner, along with Anderson .Paak, 21 Savage, Kodak Black, Lil Uzi Vert, Lil Dicky, Dave East, Denzel Curry, G Herbo and Lil Yachty. In June, Desiigner made his US television debut, when he performed his hit single "Panda", at the 2016 BET Awards.
In late June 2016, his XXL Freshman Freestyle "Timmy Turner" went viral on the internet.
On June 26, 2016, Desiigner released his first full-length project, a mixtape titled New English, on Tidal, following a live premiere of the mixtape on June 22.