A B S T R A C TObjective: To identify the medicinal plants effective in infectious diseases. Methods: Initially, we obtained a list of herbalists and traditional healers from Food and Drug Deputy. Direct observations and interviews as well as collection of herbarium specimens of indigenous medicinal plants effective in infectious diseases of urinary tract, reproductive, digestive, respiratory and skin systems were performed. This study was conducted through questionnaires and interviews; the questionnaires were distributed among traditional healers and simultaneous interviews were also run. The plants were herbariumized, herbarium specimens were authenticated, and their species were determined by using reliable flora and other sources. Finally, the data were input into Excel 2010 and analyses were performed. Results: Out of the studied plants, 35 native medicinal plants belonging to 17 families were effective in the treatment of various diseases and infections. In this study, the Lamiaceae family had the highest frequency of plants for the treatment of infections. Traditional healers of Urmia in 24% of cases used the leaves of medicinal herb to treat patients. In 68% of cases, they prescribed medicinal herbs in the boiled forms. Most medicinal herbs showed therapeutic effect on the digestive system. Conclusions: Traditional medicinal sources, valuable knowledge of traditional healers in Urmia, the scientific investigation of the effects of the herbs offered in this study and their effects in traditional medicine may provide a good source for new drugs in modern medicine.