Purpose. Comparative evaluation of the clinical and cost-effectiveness of perioperative antibiotic prophylaxis systemic fluoroquinolones cataract. Methods. A retrospective randomized trial of postoperative infectious complications after 9 314 cataract surgery performed by «small sections» technology from 2012 to 2014. Group 1 patients received 0,5% levofloxacin instillation (4 times a day for three days before surgery), 2nd group patients received additional systemic levofloxacin (oral, 500 mg / day). Relative risk (RR), relative risk reduction (RRR) and absolute risk reduction (ATS) complications, the number of patients needed to treat (NNT) were сalculated. Results. In group of patients receiving antibiotic prophylaxis just as instillation fluoroquinolones, infection rates were 0,25%, while in the group where the patients received an additional fluoroquinolone systems but - 0,02%. RR 0,08, COP - 0,92 CAP - 0,23%, NNT - amounted to 423. The costs of systemic antimicrobial prophylaxis exceeded the cost of a local antibiotic prophylaxis 1,8 times. At the same time the costs of treatment which developed endophthalmitis in 12 group 1 exceeded the value of systemic antibiotic prophylaxis and treatment of endophthalmitis after systemic use of levofloxacin. Conclusions. System use of fluoroquinolones in the perioperative period of cataract surgery is an effective method of preventing infectious tion of postoperative complications as clinical as the economic aspects.