Given article deals with the results of the study of antimicrobial activity and microbiological purity of Carduus crispus (C.C.) extracts. It has been found that 40% C.C. extract exhibits antimicrobial activity against all the bacterial culture: Gram-positive Staphylococcus aureus, Bacillus subtilis, as well as gram-negative Escherichia coli. 90% C.C. extract exhibits the same antimicrobial activity against all the bacterial culture: Gram-positive Staphylococcus aureus, Bacillus subtilis, as well as gram-negative Escherichia coli. It was established experimentally that the extract C.C. 90% has a higher degree of antimicrobial activity than the extract C.C. 40%.No activity was observed with respect to the culture of yeast-like fungus Candida albicans. Both samples meet the requirements of the Pharmacopeia of Ukraine in terms of "microbiological purity of non-sterile drugs