The parasitic wasp Agriotypus was gathered from the parasitisum nest of Goera japonica, Neophylax japonicus and Psilotreta kisoensis in Sasaya river (Takano-cho), Kogoro river (Hiwa-cho), Hiwa river (Hiwa-cho, Shobara city) and Taishaku river (Tojyo), in the northern districts of Hiroshima Prefecture. The parasitic wasp Agriotypus attacks G. japonica in Taishaku river and Hiwa river, attacks G. japonica and N. japonica in Kogoro river and Kumano river, and attacks N. japonica and P. kisoenseis in Sasaya river. As breeding 160 examples of Caddisflies attacked by the parasitic wasp Agriotypus, emerged 99 specimens 46 [male], 53[female]) of the parasitic wasp Agriotypus. Breeding terms are about 10 days to 11 months, and 21 specimens, which turned to be the nest number, were emerged after 6 months. As many the parasitic wasp Agriotypus emerged in May and September, peak of emergence is spring and autum twice a year in northern districts of Hiroshima Prefecture. There are two type of the hibernation, one is adult hibernation type, and the other is mature larvae-pupae type, and adult hibernation type is emerged in spring, mature larvae-pupae type is emerged in autumn. The parasitic wasp Agriotypus are identified Agriotypus gracilis Waterson, attacked to G. japonicus, and Agriotypus silvestris Konishi et Aoyagi attacked to N. japonicus. Two female specimens of Agriotypes sp. were emerged from P. kisoensis, they are not identified without male specimen, though they might be A. silvestris, Agriotypus silvestris Konishi et Aoyagi are newly record in Hiroshima Prefecture. Trichoptera (Insecta) : Host Goera japonica (Trichoptera) : Host Neophylax japonicus (Trichoptera) : Host Psilotreta kisoensis (Trichoptera) : Host Agriotypus (Ichneumonidae) : Parasite Agriotypus gracilis (Ichneumonidae) : Parasite Agriotypus silvestris (Ichneumonidae) : Parasite New record Reproduction; Life cycle and development; Development; Metamorphosis; Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Land zones; Palaearctic region; Eurasia; Asia Agriotypus; Reproduction; Life cycle; Life history; Emergence; Insect hosts; Life history & reproduction; Trichoptera; Japan; Honshu, Hiroshima Prefecture Agriotypus gracilis; Insect hosts; Life history & reproduction; Japan; Goera japonica (Trichoptera) Agriotypus silvestris; Insect hosts; New geographical record; life history & reproduction; Neophylax japonicus (Trichoptera); Japan; Honshu, Hiroshima Prefecture Goera japonica; Hymenopteran parasites; Parasite life history & reproduction; Japan; Agriotypus gracilis Neophylax japonicus; Hymenopteran parasites; New geographical record; parasite life history & reproduction; Agriotypus silvestris; Japan; Honshu, Hiroshima Prefecture Psilotreta kisoensis; Hymenopteran parasites; Parasite life history & reproduction; Japan; Agriotypus Trichoptera; Hymenopteran parasites; Agriotypus; Japan; Honshu, Hiroshima Prefecture none