The objective of the experiments was to determine the bacteria species isolated from the ontocenoses of the beak cavity and cloaca in the reproductive geese flocks as well as to recognize the potential dependence of the microbial spectrum on bird age, environmental conditions and season. The studies covered 17 farms of reproductive geese white Italian breed reared under differentiated conditions. The experimental material was constituted by the beak cavity and cloaca swabs (920 samples). Isolation and identification of every bacteria species was performed according to the conventional bacteriological methods with commercial tests. The obtained results were analysed statistically by t-Student test. Regardless of a sampling site (beak cavity, cloaca) the isolated bacterial flora composition included: Escherichia coli, Proteus spp., Staphylococcus spp., Streptococcus spp. and Enterococcus spp. Moreover, in single cases Bacillus spp., Citrobacter spp., Yersinia spp., Enterobacter spp. and Klebsiella spp. were identified. Each microbial species incidence was mainly contingent on the environmental conditions and the examined bird age, while to a smaller extent on the ontocenosis.