Dias or DIAS may refer to:
- Desmoteplase In Acute Stroke, a series of clinical trials investigating the clinical efficacy of desmoteplase, a thrombolytic agent, in treating acute ischaemic stroke
- Destruction in Art Symposium
- Detaşamentul de Poliţie pentru Intervenţie Rapidă (Special Actions and Interventions Detachment), a former name of Romanian police rapid response units
- Dias (surname), a common surname in the Portuguese language, namely in Portugal and Brazil. It is cognate to the Spanish language surname Díaz
- Dias, a city of ancient Lycia
- Direct Internet Access System
- Drop In Auto Sear, a device that when installed in a semi-automatic AR-15,along with M-16 fire control parts, allows selection of semi-automatic or fully automatic fire.
- Dublin Institute for Advanced Studies
- Viola (trawler), a steam trawler built in 1906 as the Viola and renamed Dias
- Dias (Δίας), the Modern Greek name for god Zeus
- Reversal film, a type of photographic film that produces a positive image on a transparent base; diafilm, diapositives