The efficacy of cycloferon in complex therapy of salmonellosis and yersiniosis in children (n=220) was investigated under clinical and laboratory conditious. It was shown, that cycloferon had direct and indirect immunotropic action in salmonellosis and yersiniosis in children. In contrast to the conventional antibiotic therapy, the use of cycloferon provided a more rapid relief of the local and systemic symptoms, reduction of superinfection or exacerbation. It had a positive effect on the antiinfective resistance of the colon mucosa resulting in normalization of the colon lumen microecology. The use of cycloferon provided eradication of the pathogen and opportunistic organisms. In the treatment of salmonellosis it enhanced formation of rare bacterial reconvalescent Shigella.