Seven xylophagous insect species were estab established in stems and branches of Salix caprea L. during the period 1998-2003 in Bulgaria: Agrilus lineola lineola Redtenbacher (Coleoptera: Buprestidae), Aromia moschata (Linnaeus), Oberea oculata (Linnaeus), Saperda populnea (Linnaeus), Saperda similis Laicharting (Coleoptera: Cerambycidae), Synanthedon formicaeformis (Esper) (Lepidoptera: Sesiidae) and Rhabdophaga clavifex (Kieffer) (Diptera: Cecidomyiidae). From them, six parasitoid species were reared: Dolichomitus mesocentrus (Gravenhorst), Dolichomitus populneus (Ratzeburg (Hymenoptera: Ichneumonidae), Stephanus serrator (Fabricius) (Hymenoptera: Stephanidae), Aprostocetus metra (Walker), Euderus caudatus (Thomson) (Hymenoptera: Eulophidae) and Billaea irrorata (Meigen) (Diptera: Tachinidae). D. populneus, E. caudatus and B. irrorata were connected with S. populnea; D. mesocentrus and S. serrator with S. similis; and A. metra with R. clavifex. Two parasitoids (A. metra and E. caudatus) had not previously been reported for the fauna of Bulgaria. The parasitoid-host relationships D. mesocentrus-S similis and S. serrator-S. similis were established for the first time in this study. Nutrition; Diet; Parasites diseases and disorders; Hosts; Insect hosts; Land zones; Palaearctic region; Eurasia; Europe Insecta; Food plants; Recorded; Plant hosts; Salix caprea; Recorded & hymenopteran & dipteran parasites recorded including new host records; Bulgaria; Species feeding on Salix (plant) recorded & parasites recorded including new host records Billaea irrorata (Tachinidae); Coleopteran hosts; Saperda populnea; Recorded; Bulgaria; Coleopteran host recorded Hymenoptera; Insect hosts; Hosts feeding on Salix (plant) recorded including new host records; Bulgaria; Insect hosts feeding on Salix (plant) recorded including new host records Stephanus serratus (Stephanidae ); Dolichomitus mesocentrus (Ichneumonidae ); Coleopteran hosts; Saperda similis; New host record; Bulgaria; New coleopteran host record Aprostocetus metra; Euderus caudatus (Eulophidae ); Bulgaria; New record none