An illustrated key to the European genera of the subfamily Opiinae (Hymenoptera, Braconidae) is presented and two new genera are described and illustrated: Cavopius gen. nov. (type species: Opius (Agnopius) daghoides Zaykov & Fischer, 1983) from West and East Palaearctic regions and Pseudosteres gen. nov. (type species: Biosteres adanaensis Fischer & Beyarslan, 2005) from West Palaearctic region. Two new species are described and illustrated: Cephaloplites gijswijti sp. nov. from Greece and Cavopius depressorius sp. nov. from S. Korea. Opius (Hypocynodus) kilisanus Fischer & Beyarslan, 2005 is a new synonym of Cephaloplites mocsaryi Szépligeti, 1897. The following new combinations are proposed: Cavopius daghestanicus (Telenga, 1950), comb. nov., C. daghoides (Zaykov & Fischer, 1983), comb. nov., Pseudosteres adanaensis (Fischer & Beyarslan, 2005), comb. nov., P. arenaceus (Jakimavičius, 1986), comb. nov., P. christenseni (Papp, 1982), comb. nov., P. pseudarenaceus (Fischer & Beyarslan, 2005), comb. nov., and P. riphaeus (Tobias, 1986), comb. nov. Keys to species are provided for Cavopius gen. nov., Cephaloplites Szépligeti, 1897, and Pseudosteres gen. nov. [ABSTRACT FROM AUTHOR]