Viscum L. is a semi-parasitic genus growing on various host plants, such as trees and shrubs. The plant is known as "Okse Otu" in Turkey. In our country, Viscum L. is represented by one species and 3 subspecies. These subspecies are V. album ssp. album, V. album ssp. abietis, V. album ssp. austriacum. Comparative investigations were carried on with the active principles, phenylpropanoid glycosides, of the subspecies of V. album.