He was a 3-year-letter wide receiver at Montgomery High School in Montgomery, Texas, and received a scholarship to Prairie View A&M University where he was switched to tight end and finally defensive line.

While at Prairie View A&M, Spears was a unanimous preseason All-SWAC first-team selection as a defensive end in 2009.

Spears was claimed by Cleveland Browns off waivers from Miami Dolphins and moved from defensive end to linebacker on September 4, 2011.

On the next day, he cleared waivers and was placed on the Colts' injured reserve list.

On September 10, 2013 the Indianapolis Colts waived linebacker Quinton Spears (hamstring) from injured reserve.