Oisín (pronounced [əˈʃiːnʲ,ˈɔʃiːnʲ], approximately USH-een) is an Irish male given name; meaning "fawn" or "little deer", derived from the Irish word os ("deer") + -ín (diminutive suffix). It is sometimes anglicized as Osheen (/ɒˈʃiːn/ OSH-een) or spelt without the acute accent (fada), as Oisin.

Variants in other languages include Scottish Gaelic: Oisean (pronounced [ˈɔʃan]), Welsh: Osian and English: Ossian.

• Oisín, legendary Irish poet
• Oisín Fagan (born 1973), Irish professional boxer
• Oisín Gallen, Irish Gaelic footballer
• Oisín Gough (born 1989), Irish hurler
• Oisín Kelly (1915–1981), Irish sculptor
• Oisín Kelly (born 1997), Irish hurler
• Oisín Mac Diarmada (born 1978), Irish fiddler
• Oisín McConville (born 1975), Irish Gaelic footballer
• Oisin McEntee (born 2001), Irish footballer
• Oisín McGann (born 1973), Irish writer and illustrator
• Oisín Mullin (born 2000), Irish footballer
• Oisin Murphy (born 1995), Irish jockey
• Oisín Quinn (born 1969), Irish politician
• Oisín Stack, Irish actor

• List of Irish-language given names