DSO may refer to:
- Decorations
- Distinguished Service Order (disambiguation) refers to a number of decorations
- Music
- Dallas Symphony Orchestra
- Dark Star Orchestra
- Deathspell Omega, a French black metal band
- Detroit Symphony Orchestra
- Deutsches Symphonie-Orchester Berlin
- Diablo Swing Orchestra
- Dartmouth Symphony Orchestra, one of the Dartmouth College student groups and the resident orchestra of the Hopkins Center for the Arts
- Computers and electronics
- Digital Sampling Oscilloscope, samples measurements and displays or stores them
- Digital storage oscilloscope
- Dynamic Shared Object, a library of subroutines in Unix-like systems
- Entertainment
- Dark Sun Online
- Dark Star One
- Other
- Days Sales Outstanding
- Deep sky object
- Defence Science Organisation, now known as DSO National Laboratories, Singapore
- Defense Sciences Office (DARPA), one of the seven program offices of the US Defense Advanced Research Projects Agency
- Digital switch-over, the transition from analogue to digital television transmission. See: Digital television transition
- Direct Shipping Ore, referring to iron ore that can be shipped directly to a steel furnace
- Directorate of Special Operations, South African law-enforcement agency
- Direct service organisation, a business unit of a United Kingdom local authority
- Distribution system operator in the electricity supply industry
- Diving safety officer
- Division Special Operations (Germany) (Division Spezielle Operationen), part of Germany's Bundeswehr
- Dubai Silicon Oasis, corporate free zone in UAE
- Groupe DSO, Australian headquartered business cooperative