A new fossil species of the silvanid flat bark beetle genus Cathartosilvanus Grouvelle is described and illustrated from Upper Eocene Rovno amber. Cathartosilvanus perkovskyi sp. nov. resembles extant C. opaculus (LeConte, 1854) and differs from extinct congeners from Baltic amber in pronotal lateral sides crenulate, pronotum as long as wide, and elytral intervals partially convex. It is the first report of Silvanidae from this Lagerstätte.