The antituberculous activity of a nanocomposite based on nanoparticulate silver and isoniazid has been studied on the model of drug-resistant tuberculosis in a group of 65 white mice. The possibility of overcoming the resistance of the tuberculosis activator by the proposed nanocomposite of isoniazid and nanoparticulate silver is demonstrated in terms of the survival index, biometric data, bacteriological and pathomorphological parameters. Dose-dependent parameters of the presence of nanoparticulate silver in the composite structure are established. The results of preclinical research scientifically prove good prospects for using nanoparticulate silver in the treatment of drug-resistant tuberculosis.