Benjamin David Gillies (born 24 October 1979) is an Australian musician, best known as the drummer of successful rock band Silverchair, which has sold over 6 million albums worldwide and has had more Top 20 hits during the last decade than any other Australian artist.

Gillies was born in Newcastle, New South Wales. His mother Annette Gillies worked in the cafeteria at Newcastle High School and his father, David Gillies, works as a plumber. He has an older sister named Kristie and Gillies' first cousin is Channel 7 TV presenter, Kylie Gillies. The Gillies family is a part of the Surfrider Foundation, which promotes clean ocean water. Gillies was a quad drummer in The Marching Koalas and he taught his friend Chris Joannou of Silverchair how to play bass in three months. Gillies also plays the guitar and bass.

In 2002, Silverchair was severely affected by the band’s inability to tour or do promotional appearances due to Daniel Johns' ill health. The singer/guitarist spent 2002 battling a severely debilitating case of reactive arthritis from which he is now recovering. In November of 2005, Silverchair announced they were working on the music for their 5th studio album Young Modern, released in Australia on March 31, 2007. During this period Gillies was a member of an Australian rock band Tambalane which has now broken up due to Silverchair's return.

Gillies performed a song with Silverchair originally written by Midnight Oil at the 2006 ARIA Awards as part of Midnight Oil's induction into the ARIA Hall of Fame where he sang back up vocals.

During his down time within the Freak Show timeline, Gillies worked in a record store to gain as much musical knowledge as possible. After listening to jazz he began to incorporate its style into the writing of Neon Ballroom.