DTO may refer to:

• Data transfer object
• Detailed Test Objective, an experiment to be performed by NASA in space
• Download to own
• Deodorized tincture of opium
• Diluted tincture of opium
• Disruptive Technology Office
• Disney's Toontown Online
• Driverless train operation
• Drug trafficking organizations
• Domestic terrorist organization
• Denton Municipal Airport (IATA and FAA airport codes)
• "D.T.O.": a song on Vision of Disorder (album), the self-titled debut by the American metalcore band
• Denkmäler der Tonkunst in Österreich (Monuments of Fine Austrian Music), a book series