Thomas Matthew DeLonge (; born December 13, 1975) is an American musician best known as the co-founder, co-lead vocalist, and guitarist of the rock band Blink-182 across three stints: 1992 to 2005, 2009 to 2015, and again since 2022. He is also the lead vocalist and guitarist of the rock band Angels & Airwaves, which he formed in 2005 after his first departure from Blink-182. DeLonge is noted for his distinctive nasal singing voice.

DeLonge received his first guitar as a child and later began writing punk rock songs. While in high school, he formed Blink-182 with bassist Mark Hoppus and drummer Scott Raynor. They signed with Cargo Music and released their debut album, Cheshire Cat (1995), which made them popular in the local scene. Their second album, Dude Ranch (1997), was released by MCA Records and featured the hit single "Dammit". Raynor was replaced by Travis Barker in 1998 and the group achieved widespread success with their third album, Enema of the State (1999), which featured three hit singles; it sold upwards of 15 million copies worldwide and went quadruple-platinum in the U.S. The band's fourth release, Take Off Your Pants and Jacket (2001), gave them their first No. 1 album.

DeLonge and Barker experimented with post-hardcore music on the album Box Car Racer (2002), which they released under the name Box Car Racer, but the side project was dissolved the following year. Blink-182's untitled fifth album, also known eponymously as Blink-182 (2003), reflected a change in tone within the group; two years later, following internal tension spearheaded by DeLonge, the band broke up for a few years. DeLonge then formed Angels & Airwaves, which has since released five albums and has evolved into what he calls an "art project" encompassing various forms of media.

Outside of music, DeLonge has founded companies such as Macbeth Footwear, which sells vegan and organic clothing; Modlife, which sells technology designed to help artists monetize their creations; and To the Stars, which is dedicated to the exploration of fringe science. He scored and produced the sci-fi film Love (2011), has multiple film projects in development, and wrote the children's book The Lonely Astronaut on Christmas Eve (2013).