RIS may refer to:

• Radio Information Service, a reading service for the blind in Pittsburgh, Pennsylvania
• Radiology Information System, device used to manipulate and distribute patient radiological data imagery
• Rail Integration System, a feature on many modern-day guns which allows for sights and scopes to be "snapped in"
• Relational Interface System, a database access interface
• Remote Installation Services, a Microsoft Windows service that allows a remote server to act as a custom installation disk
• Reparto Informazioni e Sicurezza, a military intelligence agency of Italy, see SIOS
• Republik Indonesia Serikat (The Republic of the United States of Indonesia)
• Réseau Info-Sports, the original name of RDS Info, a sports broadcaster in Canada
• Reservoir Induced Seismicity
• Reverse image search (TinEye engine)
• Reviving the Islamic Spirit, a major annual Islamic conference in Canada
• RIS (file format), (from Reference Information Systems), a standardized bibliographic data file format
• RIS Delitti Imperfetti, an Italian television series
• Reparto Investigazioni Scientifiche, (en. "Scientific Investigation Section"), the forensic science unit of the Arma dei Carabinieri
• R. I. S. – Die Sprache der Toten, a German television series
• R.I.S, police scientifique, a French television series
• Rishton railway station, England; National Rail station code RIS
• Roosevelt Intermediate School, an Intermediate School in Westfield, New Jersey
• Routing Information Service project of RIPE NCC
• Ruamrudee International School, an International School located in Bangkok, Thailand
• Russian Imperial Stout, a type of dark beer

Ris may refer to the following:

• Ris, Puy-de-Dôme, a commune in the Puy-de-Dôme department, France
• Ris, Hautes-Pyrénées, a commune in the Hautes-Pyrénées department, France
• Ris, Norway
• Diane Ris (1932–2013), Catholic nun, educator and author
• Friedrich Ris (1867–1931), Swiss physician and entomologist
• Sweetbread, a type of offal, also known as ris

RIS is a standardized tag format developed by Research Information Systems, Incorporated (the format name refers to the company) to enable citation programs to exchange data. It is supported by a number of reference managers. Many digital libraries, like IEEE Xplore, Scopus, the ACM Portal, Scopemed, ScienceDirect, and SpringerLink, can export citations in this format.