The purpose of this study was to evaluate the quality medicinal plant species traded in Londrina, Parana state, Brazil. Medicinal plants were chosen on the basis of secretory structures or storage facilities of the active ingredients such as leaves, bark, flowers and fruits. Plant species chosen to perform the analyzes were phytosanitary quality: chamomile (Chamomilla recutita L. Rauschert), peppermint (Mentha piperita), anise (Pimpinella anisum L), hibiscus (Hibiscus sabdariffa L.), cinnamon (Cinnamomum zeylanicum Blume) and lemon balm (Melissa officinalis L.). The plant materials were purchased by five points or shops in city.Were identified microorganisms harmful to human health as Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus, Fusarium sp, Nigrospora sp, Penicillium sp, and Rhizopus sp. The six medicinal species acquired in trade from Londrina lower microbiological quality of medicinal plant. There is a high incidence of fungi harmful to human health as Aspergillus flavus and Penicillium sp in the six medicinal plants collected within five points of marketing.