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 (Диас), a Soviet first name, which became widespread in honour to Spanish communist politician José Díaz
• Dias (Lycia), a city of ancient Lycia
• Direct Internet Access System
• 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
• Dias (ΔΙ.ΑΣ), a police motorcycle unit of the Hellenic Police
• Reversal film, a type of photographic film that produces a positive image on a transparent base; diafilm, diapositives
• Copernicus Data and Information Access Services (DIAS), a European Commission initiative aimed at facilitating and standardizing access to satellite data.
• Dias (mythology), two figures in Greek mythology