The work deals with metamorphic petrology of the rock complexes forming the Pozdišovce-Iňačovce Unit. They are thick complexes of metasediments intercalated by stratiform metaultramafic intrusions and layers of metavolcanic rocks, the "Bündnerschiefer" lithology of which indicates that they belong to the Penninicum. In the phyllitic rocks the determination of metamorphic conditions was based on the study of mineral assemblages. They can be divided into two groups: non-diagnostic: Mu + Pa + Qz ± Ch ± Ab ± Om, stable under very low as well as low-grade metamorphic conditions; diagnostic: Mu + Pa + Py + Qz, Ch + Ctd + Qz. Diagnostic, and mineral assemblages indicate that greenschist facies conditions were reached. The assumed maximal temperatures were between 300–400 °C (depending on the composition of coexisting fluid phase). The mineral assemblage Ctd + Py is characteristic for the low to medium pressure range of the lower greenschist facies (Winkler 1979).