Frequency of postoperation complications at oncological patients deviates in the range from 10 to 70 per cent. The highest frequency of infectious complications is registered after extended and complex operations (cervical carcinoma, cancer of vulva, ovarian cancer). The most frequent aerobic pathogens in oncology are enterococci, staphylococci and streptococci, in the case of urinary tract operations--enterococci and Erscherichia coli. Perioperation prophylaxis with amoxycillin/clavulanate (Augmentin) effective against this microorganisms and also against anaerobic bacteria (usual pathogens of post operation infections in oncogynecology) resulted with lower frequency of wound infections. Demonstrated prophylaxy efficacy was more potent than that of cefotaxime (p < 0.05) or when compared to results of other antibiotics administration after operations only.