Despite the high level of resistance of E.coli as the main causative agent of urinary tract infections, fluoroquinolones are among the most frequently used antimicrobial agents in empirical therapy of uroinfections. Aim. Clinical and economic evaluation of the effectiveness of different antibacterial strategies of community-acquired uncomplicated acute pyelonephritis with the predicted dynamics of resistance of E.coli as the main causative agent of uroinfections. Materials and methods. The calculations take into account the literature data on the effectiveness and safety of the starting regime of antibacterial therapy of uncomplicated pyelonephritis with cephalosporins of the 3rd generation, fluoroquinolones, aminoglycosides and carbapenems in terms of hospital specialized medical care. The model of «decision tree» is constructed. A list of direct and indirect costs was compiled, on the basis of which the cost of 1 case of acute uncomplicated pyelonephritis therapy for each strategy of antibacterial therapy was calculated. The «cost-effectiveness analysis» and budget impact analysis were performed. Results. The cost of 1 case of therapy with acute uncomplicated pyelonephritis gentamicin was the lowest in comparison with alternative strategies (33 679,89 rubles). Cost-effectiveness analysis showed that the strategy of antibacterial therapy of acute uncomplicated pyelonephritis with gentamicin dominated alternative strategies: at lower costs, it was also more effective. Summary. For a more accurate calculation of clinical and economic efficiency of antimicrobial agents it is necessary to monitor the dynamics of the resistance level in the territory of the Russian Federation.