This paper presents data on screening of antimicrobial properties of extracts from the raw materials (18 plants) containing alkaloids. The microbiological method of studying antimicrobial properties of extracts, agar well diffusion method, has been applied; special mathematic method of comparison of antimicrobial properties of extracts vector theory has been applied. The most active extracts have been selected; they have antimicrobial activity of medium strength: from Phellodendron amurense bark; Macleaya cordata herb; Nuphar lutea root; Corydalis marshal tubers; Belladonna herb; Solanum dulcamara herb and fruits. A potential to use in practice of the extracts obtained from Echinops sphaerocephalus seeds and Cynoglossum herb as antimicrobial medicinal products has been shown. Low levels of antimicrobial activity have been demonstrated by the extract obtained from Peganum harmala herb. Data show significant antimicrobial properties of numerous kinds of raw materials that contain alkaloids and high possibility of their use in complex phytochemical medicinal products, but with certain restrictions and thorough side effect examination.