Robert O'Neil "Bob" Forrest (born February 15, 1961) is the lead vocalist and lyricist for Los Angeles bands Thelonious Monster and The Bicycle Thief. In September 2006 he released his first solo album, Modern Folk And Blues Wednesday. He is also a drug counselor, appearing alongside Dr. Drew Pinsky on Celebrity Rehab and Sober House. He contributed the song "Moonshiner" to the I'm Not There soundtrack.

Forrest is the former Chemical Dependency Program Director at Las Encinas Hospital. In 2010, he and co-founder Shelly Sprague launched Hollywood Recovery Services.