Ejnar is a masculine given name and may refer to:
Ejnar Emborg (1888–1963), Danish composer
Ejnar Hertzsprung (1873–1967), Danish chemist and astronomer
Ejnar Jacobsen (1897–1970), Danish composer
Ejnar Mikkelsen (1880–1971), Danish polar explorer and author, born in Jutland
Ejnar Mindedal Rasmussen (1892–1975), Danish architect
Ejnar Olsson (1896–1925), Swedish ice hockey player
Ejnar Tønsager (1888–1967), Norwegian rower
Ejnar Torgensen (1900–1932), Norwegian sailor