Abstract: Introduction: Following the introduction in 2006 of the National Policy on Integrative and Complementary Practices, and The National Policy on Medicinal Plants and Herbal Medicines, the Municipal Secretariat for the Environment of the City Hall of Sao Paulo initiated the Medicinal Plants Course, later expanded to The Medicinal Plants and Herbal Medicines Course for the training of health professionals. This study aimed to evaluate the impact of the 2014 and 2015 edition of the course “Medicinal Plants and Herbal Medicines” on health professional practices. Methods: An exploratory and descriptive study was conducted with a qualitative-quantitative approach. The quantitative process (Phase I) consisted of a questionnaire being emailed to health professionals who were involved in the course, divided into seven categories: biomedical professional, dental surgeon, nurse, pharmacist, physiotherapist, physician and nutritionist; and, out of 165 questionnaires, 114 responses were received (69.1%). The Qualitative and Quantitative process (Phase II), comprised semi-structured, in-person individual interviews to obtain detailed information on Phytotherapy practices, with 73 health professionals being interviewed, before and after the training, comparing their practices afterwards. Results: The course had a positive impact on the acceptance and application of Phytotherapy by health professionals with a significant increase (p<0.001) in the expansion of activities related to Phytotherapy (herbal tea “meetings”, medicinal herb gardens and capacity training), regarding the use of herbal products, such as Matricaria chamomilla (chamomile), Maytenus ilicifolia (espinheira-santa), Valeriana officinalis (valeriana). An increase in the knowledge of Phytotherapy risks was also observed, although there was no increase in the reporting of adverse reactions. The study confirmed the importance of the inclusion of Medicinal Plants and Herbal Medicines Courses as part of undergraduate and postgraduate school, as well as the technical training and continuing education for SUS health professionals. Conclusion: The positive impact found out in almost all evaluated aspects, such as the increase in the knowledge and in the prescription of herbal medicines, confirms the importance of such courses. The results suggest the training promoted a positive impact on the Phytotherapy practice of the Public Health System professionals in São Paulo.