The present work discusses composition and structure of the Oligochaeta community of the Danube river in the Belgrade region, Serbia, as determined in investigation of the bottom fauna in May and October of 2004. The investigated region encompassed five locations along 66 km of the river s course. Sixteen species of Oligochaeta (12 genera; 3 families) were determined in the spring, while 12 species (8 genera; 2 families) were found in the autumn aspect of the assemblages. Aquatic worms made up the majority component of the bottom fauna in the investigated part of the river, both in regard to the number of species present in the fauna and with respect to their abundance. The following species were found most frequently at the investigated locations in May and October: Limnodrilus hoffmeisteri C l a p a r e d e , 1862; L. claparedeanus R a t z e l, 1868; L. udekemianus C l a p a r e d e, 1862; L. profundicola V e r r i l l, 1871; Tubifex tubifex M ü l l e r, 1774; Psammoryctides albicola M i c h a e l s e n, 1901; Branchiura sowerbyi B e d d a r d; and Potamothrix hammoniensis M i c h a e l s e n, 1901. In view of the fact that Belgrade is an important urban and industrial centre, the influence of organic pollution on the oligochaete and benthic communities as a whole was taken into consideration. The Sřrensen s Quotient of Similarity was determined to compare benthic assemblages of the investigated locations.