Dayana is a given name. Notable people with the name include:

• Dayana (pronunciation d̪ɪɑɴɑ, Language Hebrew, the Judge) variant of the given name Diana
• Dayana Cadeau (born 1966), Haitian-born Canadian American professional bodybuilder
• Dayana Cázares (born 1999), Mexican football midfielder
• Dayana Colmenares (born 1984), Miss Venezuela International 2007
• Dayana Garroz (born 1978), Venezuelan actress
• Dayana Kirillova (born 2002), Russian singer
• Dayana Martinez (born 1986), Venezuelan épée fencer
• Dayana Mendoza (born 1986), Venezuelan Miss Universe 2008 and contestant on Celebrity Apprentice
• Dayana Rodríguez (born 2001), Venezuelan footballer
• Dayana Yastremska (born 2000), Ukrainian professional tennis player

• Laudakia dayana, species of Agamid lizard found in Haridwar, India
• Sophronitis dayana, species of orchid endemic to Brazil (southern Minas Gerais to Rio de Janeiro)

• Dayan (witch) or dayana, a witch or vengeful female spirit in Indian culture

• Dayan (disambiguation)