AbstractThree native species of parasites and 3 hyperparasites were reared from pupae of the European winter moth, Operophtera brumata (L.), and the Bruce spanworm, O. bruceata (Hulst), collected in the Victoria area of Vancouver Island, British Columbia, in 1981. Two of the pupal parasites also attacked other species of Geometridae. Two species of hyperparasites attacked Cyzenis sp., and the third parasitized ichneumonid primary parasites of Operophtera spp. The hyperparasites may have a negative impact on the biological-control agents, Cyzenis albicans (Fall.) and Agrypon flaveolatum (Grav.). Total parasitism by pupal parasites of the Operophtera host complex was about 4%. Descriptions and illustrations of cephalic structures of final-instar larvae of the parasites and a key for their separation are given.