Dennis Dias (born December 12, 1946) is an American guitarist, best known for being a founding member of Steely Dan.

Dias was working with his own band out of his garage in Hicksville, New York, when he placed an ad in The Village Voice^[1] in the summer of 1970 that read: "Looking for keyboardist and bassist. Must have jazz chops! Assholes need not apply".^[2] Donald Fagen and Walter Becker responded to the advertisement.

They joined his band and immediately began playing their own material. Dias fired the rest of the band, and the three of them moved to California, adding drummer Jim Hodder, guitarist Jeff "Skunk" Baxter, and vocalist David Palmer before recording for ABC/Dunhill Records as Steely Dan. Dias recorded as a permanent member of the band on 1972's Can't Buy a Thrill (with an electric sitar solo on the song "Do It Again"), on 1973's Countdown to Ecstasy, and on 1974's Pretzel Logic.

Following a tour promoting Pretzel Logic, Becker and Fagen decided to break the band up and use session musicians on future albums. Though no longer a member of the band, Dias continued to work with them as a session guitarist, appearing on 1975's Katy Lied, 1976's The Royal Scam, and 1977's Aja. In 1991 he joined Toto on their Summer Festival Tour. He also recorded with Wayne Shorter, Wilfrido Vargas and Pete Christlieb. Some of Dias's original material was recorded on a 1999 CD called Matter of Time, with Lisa Jason (Vocals) and Andy Bergsten (Bass) as the core of the band.^{[citation needed]}

In 2014, he was playing with Denny Dias and Friends, a Boston-based band formed with Lisa Jason and Andy Bergsten with session musicians from around the country. In 2015, they planned a tour that included the Iridium in NYC.^{[citation needed]}

With Steely Dan

• Can't Buy a Thrill (ABC, 1972)
• Countdown to Ecstasy (ABC, 1973)
• Pretzel Logic (ABC, 1974)
• Katy Lied (ABC, 1975)
• The Royal Scam (ABC, 1976)
• Aja (ABC, 1977)

With others

• Soundtrack to You've Got to Walk It Like You Talk It or You'll Lose That Beat (1971) with Walter Becker and Donald Fagen, credited as Denny Diaz
• David Garfield and Friends, Tribute to Jeff (Intercord, 1997)

• Denny Dias at AllMusic
• Denny Dias discography at Discogs