Roseum may refer to:
- Calyptridium roseum, a synonym for Cistanthe rosea, a flowering plant species
- Catasetum roseum, a synonym for Catasetum lemosii, an orchid species
- Dendrochilum roseum, a synonym for Dendrobium crepidatum, an orchid species
- Dipodium roseum, an orchid species
- Epilobium roseum, a plant species in the genus Epilobium
- Eriogonum roseum, the wand buckwheat, a wild buckwheat species
- Fusarium roseum, a synonym for Gibberella zeae, a plant pathogen which causes fusarium head blight, a devastating disease on wheat and barley
- Gliocladium roseum, a synonym for Clonostachys rosea f. rosea, a species of fungus in the family Bionectriaceae
- Laeticorticium roseum, a fungus that is a plant pathogen that decays the wood of peach and nectarine trees
- Micrommata roseum, a synonym for Micrommata virescens, a spider of the huntsman spider family, Sparassidae, with a palearctic distribution
- Solanum roseum, a plant species endemic to Bolivia
- Stephopoma roseum, a sea snail species
- Scindalma roseum, a synonym for Fomitopsis rosea
- Stylidium roseum, a synonym for Stylidium tenellum, a plant species
- Trichonema roseum, a synonym for Romulea rosea, a herbaceous perennial species
- Trichothecium roseum, a plant pathogen species
- Xanthosoma roseum, an ornamental plant in the genus Xanthosoma
- Xenophyllum roseum, a species of flowering plant found only in Ecuador