Keys are given to the European genera and species of the Pamphiliidae (Symphyta: Megalodontoidea). Ten species are added to the list of the Dutch Hymenoptera. Cephalcia alashanica europaea Benes, 1976 is synonymized with C. a. alashanica Gussakovskij, 1935 (syn. nov.), Acantholyda parvula Zirngiebl, 1937 with A. laricis (Giraud, 1861) (syn. nov.), Cephaleia intermedia Hellén, 1948 with Cephalcia lariciphila (Wachtl, 1898) (syn. nov.), and Pamphilius hortorum bicinctus Benson, 1945 with P. hortorum (Klug, 1808) s.s. (syn. nov.). Pamphilius nigricornis Snellen van Vollenhoven, 1858 is provisionally treated as a valid species (stat. nov.) Caenolyda binaghii Pesarini & Pesarini, 1976 (stat. nov.) is upgraded to species level. Some data on biology and habitats are added. Additionally, Pamphilius viridipes spec. nov. is described from The Netherlands and Acantholyda teunisseni spec. nov. from Spain.