Bacteria of the genus Enterococcus are mainly commensals building natural microflora in the digestive tract of birds and mammals. They belong to the potentially pathogenic microorganisms. Among poultry, infections caused by enterococci were reported in chickens, turkeys, ducks and ostriches. The aim of this study was to evaluate the occurrence of enterococci in poultry in Poland, including identification of enterococcus species composition and determination of the age of birds. The analysis was based on data obtained from 2014-2015 from Division of Avian Diseases at Warsaw University of Life Sciences-SGGW and four veterinary laboratories in Poland: Lab-Vet, Tarnowo Podgórne; SLW Biolab, Ostróda; Vetdiagnostica, Solec Kujawski; Vet-Lab Brudzew. Seven enterococcal species were isolated from broiler chickens (CB), commercial layers (CL), and broiler breeder flocks (BB), nine from all poultry types (chickens, turkey, ducks and geese). The most often isolated enterococci from CB were E. faecalis (57%) > E. cecorum (7%) > E. faecium (5.2%) > E. hirae (3.6%) > E. gallinarum (2.5%) > E. casseliflavus (0.7%) > E. durans (0.2%). Seven Enterococcus species were isolated from sources associated with poultry, most often E. faecalis > E. faecium > E. cecorum > E. hirae. The differences in the occurrence of particular enterococcal species were observed between CB, BB and CL. The mean age at the time of isolation of E. cecorum was approx.: 3.6 weeks in CB, 27.5 weeks in BB, 33.3 weeks in CL, 12.9 weeks in turkeys, 3.6 weeks in ducks, 39.5 weeks in geese. E. faecalis and E. faecium dominated in samples obtained from hatching eggs, dead-in-shell embryos and from samples related to poultry environment. In conclusion, this study indicates the high prevalence of bacteria of the Enterococcus genus in poultry. The present findings demonstrate the differences in Enterococcus species between poultry groups, including with regard to age. In total 10 enterococcal species (E. faecalis, E. cecorum, E. hirae, E. faecium, E. gallinarum, E. casseliflavus, E. durans, E. avium, E. thailandicus, E. aquimarinus) were detected in poultry, poultry environmental samples, hatching eggs and dead-in-shell embryos. Enterococcus faecalis and E. cecorum were found in all above-mentioned sources.