The research on the repellent effect of Tanacetum vulgare L. on Colorado potato beetle (Leptinotarsa decemlineata Say) was conducted in 1997-2000. The results, which were obtained from the laboratory and field examinations, showed a good effectiveness against beetles as well as their individual development stages. Powdered leaves and flowers of the plant both in powdered form and in water slurry were used in the experiments. Due to the lack of its toxic effect on man, T. vulgare can be used in small potato plantations near settlements as well as in ecological farms.