Robert Emile DeLeo (born February 2, 1966) is an American musician, best known as the bassist for rock band Stone Temple Pilots.

In 1985, Scott Weiland and his friends in their band Soi Disant – guitarist Corey Hicock and drummer David Allin – first encountered Deleo playing live at various gigs, deciding to track him down after witnessing his shows.

Although sales of their records exceeded over 30 million, the band disbanded due to Weiland's ongoing problems with drug abuse.

On October 8, 2013, they released an EP entitled High Rise with new lead singer Chester Bennington of Linkin Park fame.

During Stone Temple Pilots' hiatus in 1997 due to Weiland's run-ins with the law, DeLeo, his brother Dean, and Kretz joined with singer Dave Coutts of Ten Inch Men and formed Talk Show.

After Stone Temple Pilots' break-up in 2003, DeLeo and his brother Dean joined Filter frontman Richard Patrick and drummer Ray Luzier to form the band Army of Anyone.

He also contributes bass to five songs on their 2019 album New Love, including "Rain & Dream" which also features Joe Perry.

On September 29, 2022, DeLeo announced his debut solo album Lessons Learned and released its lead single "Love is Not Made of Gold", featuring Jimmy Gnecco, the same day.

[7] DeLeo is known for his smooth style of playing, with infusions of jazz, '60s rhythm and blues, and hard rock creating a distinctive tone.