Actual problems of organization and performance of chemoprophylaxis and chemotherapy of surgical opportunistic infections are discussed with an account of the main principles of and new approaches to the use of antibacterial drugs. The analysis of the authors' observations showed that the pre- and postoperative use of parenteral antibacterial drugs such as cephalosporins (cefazolin and ceftriaxone) and their combinations with aminoglycosides, the simultaneous use of beta-lactams and lysozyme, the local application of new ointments based on polyethylenglycol, foaming agents and gentacycol were prophylactically efficient in patients with high risk of surgical infections. Endolymphatic administration of gentamicin and cefotaxime was highly efficient in the treatment and prophylaxis of severe surgical infections with lymphogenous dissemination of the pathogen or its risk. In the prophylaxis of endogenous infections special attention should be paid to the suppression of the opportunistic intestinal microflora by the use of fluorquinolones and selective decontamination followed by the correction of the intestinal microbiocenosis with probiotics (bifidobacteria), lysozyme and immunological lactoglobulins as dosage forms or dry milk biologically active additives to children diet and dietotherapy.