To investigate the silk proteins of wild insects, sericin-like protein of the cocoon fibers of the parasitic wasp Apanteles glomeratus was extracted and its biochemical properties determined. Size exclusion chromatography showed that there exist two components having molecular masses of 25 and 15 kDa, each of them has amino acid composition similar to that of Bombyx mori sericin. The finding of small size sericin-like proteins, which are only one tenth of that of B. mori, is interesting in the scope of evolution of sericin protein. AI: Y BT: Biochemistry-; Ecology-; Animal-constructions Apanteles-glomeratus ( Braconidae- ) : Proteins-, Sericin-like-protein, Cocoons- ST: Braconidae- : Ichneumonoidea- , Terebrantia- , Apocrita- , Hymenoptera- , Insecta- none