异营生物（英语：heterotroph）指不能直接以无机物合成有机物，必须摄取现成的有机物来维持生活的生物。异营包括捕食、寄生和腐生三种。

A heterotroph (/ˈhɛtərəˌtroʊf, -ˌtrɒf/; ἕτερος heteros = "another", "different" and τροφή trophe = "nutrition") is an organism that cannot fix carbon and uses organic carbon for growth. Heterotrophs can be further divided based on how they obtain energy; if the heterotroph uses light for energy, then it is considered a photoheterotroph, while if the heterotroph uses chemical energy, it is considered a chemoheterotroph.