Aaron Francis Lewis (born April 13, 1972) is an American singer, songwriter, and musician who is best known as the lead vocalist, rhythm guitarist, and founding member of the post-grunge/alternative metal band Staind, with whom he released eight studio albums. Since 2010, he has pursued a solo career in country music with his debut EP, Town Line, which was released in 2011. Lewis's first full-length solo release, The Road, was released by Blaster Records in 2012.

In 2006, Lewis was ranked at number 49 in the "Top 100 Heavy Metal Vocalists" by Hit Parader.

Lewis was born in Rutland, Vermont, to a Jewish mother and a Catholic father of Italian, English, and Welsh descent. At the time of his birth on April 13, 1972, his parents were living in a log cabin. Lewis moved to New Hampshire when he was 8, and lived there until he was 12. When his parents split up, he moved with his father to Longmeadow, Massachusetts, where he attended Longmeadow High School. He also lived in Forest Park, Springfield, Massachusetts.

Aaron Lewis is the founding lead vocalist and rhythm guitarist for the rock band Staind, a role he has held since the band's formation in Springfield, Massachusetts, in 1995. His work with the group is defined by his distinctive "screaming" and melodic vocal style, which became a staple of the nu metal and post-grunge eras.

Lewis helped form Staind in 1995. The band gained significant attention after being discovered by Limp Bizkit's Fred Durst.

He has released eight studio albums with the band, including the 5x platinum Break the Cycle (2001) and their most recent release, Confessions of the Fallen (2023).

Lewis with Staind is the voice behind some of the most played songs in modern rock radio history, most notably "It's Been Awhile", which spent 20 weeks at number one on the rock charts.

He is the primary songwriter for the band, often writing hits like "Outside" and "It's Been Awhile" years before their official release.