none. The first investigations of the entomophagous of European Corn Borer in Yugoslavia date from the beginning of the 1920's of this century, when the International laboratory for this pest investigations was formed in Zagreb. With more or less details, the following entomophagous organisms of European Corn Borer were investigated in Yugoslavia: Lydella thompsoni Hrt., Pseudoperichaeta nigrolineata Walker (= Zenillia roseanae Brauer & Berg.), Eumea mitis Meigen, Clemelis pullata Meigen (Dip.: Tachinidae), Sinophorus alkae Ell. & Sact. (= Campoplex alkae Ell. & Sact.), Eriborus terebrans Graves (= Diadegma terebrans Graves, Horogenes punctorius Roman), Exerister roborator Fab., Exetastes illusor Fab., Pimpla instigator F. (Hym.:Ichneumonidae), Simpiesis viridula (Thomson) (=Eulophus viridulus Thomson) (Hym.:Eulophidae), Bracon hebetor Say (=Microbracon brevicornis Wesm.), Macrocentrus linearis Wesm. (Hym.:Braconidae), Trichogramma evanescens Westwod (Hym. :Trichogrammatidae), Myrmica laevinodis Nyl. i Lasius emarginatus Oliv. (Hym. :Formicidae), Coccinella septempunctata (L.) (Col.:Coccinellidae), Chrysopa vulgaris Sch. (Neuroptera:Chrysopidae), Trombidium (Alothrombium) fuliginosum Herm. (Acarinae:Trombididae), Hirunda rustica and Careus frugilegus (Aves). The special attention was payed to the following caterpillar parasites by our investigators: L. thompsoni, S. alkae, E. terebrans, S. viridula, B. hebetor and M. linearis and to the egg parasite T. evanesces. For the tachine L. thompsoni and the wasps S. alkae and S. viridula, the unsynchronism in the growth with their host range was proved, in contrast to E. terebrans, which completely coincides at the growth with the European Corn Borer caterpillars. The plants of maize, broomcorn, pepper, pigweed, thron apple, burdock and wormwood were the most attractive for L. thomsoni. This species is especially numerous in maize hybrids of full vegetation (FAO 600 and FAO 700). S. alkae parasited most frequently the Europian Corn Borer caterpillars, which fed and grew in the plants of hemp, eggplant, hops, thorn apple, burdock and wormwood. On the maize plants it is more numerous at the hybrids of the full vegetation period. S. viridula is dominant parasite of European Corn Borer caterpillars, which fed and grew in the plants of hemp, millet and foxtail millet, and it is also frequent at the plants of eggplant, hops, thorn apple, burdock and wormwood. Maize as European Corn Borer host plant, also manifested low attractiveness for this useful insect. In the natural conditions, the whole B. hebetor growth is completed in 2 weeks. In these conditions, the imago of the wasp lives around 10 days. The larvae of M. linearis grow in group in caterpillar skin, where they fed as ectoparasites. The pupal stage lasts 15 - 19 days. The imago flies out at the end of June and at the beginning of July at the time of the flight of European Corn Borer. All parasite individuals grown in the host individual are of the same sex, which points to poliemronia. T. evanescens is endofagous parasite with very expressed polifagousity. In the region of Backa Palanka, the total course of 1975-77 was 4,95%, 6,00% and 3,99%. Slightly lower parasity was proved on hemp (3,20%, 7,44%, 4,96%) and on hops (2,97%, 0,97%, 2,81%).