Toxicity of the essential oils extracted from Artemisia dracunculus L., Crambe orientalis L., Hypericum perforatum L, Hypericum scabrum L., Rosmarinus officinalis L, Salvia multicaulis Vahl, S. sclarea L. and Tanacetum agrophyllum (L.) were tested against adults of the Colorado potato beetle (CPB), (Leptinotarsa decemlineata Say) under laboratory conditions. Doses of 10, 15 and 20 mu l were applied and mortality of adults was determined at 24, 48, 72 and 96 h. The toxic effect was influenced by the doses and the exposure time of the 8 plant essential oils. All the tested essential oils had toxic effects against the adults of CPB. Essential oils of R. officinalis and T. agrophyllum were the most effective ones within the first 24 hrs at their lowest dose applications. In the 10 and 20 mu L\ptri doses, after 96 hrs of treatments, 88.8 and 100% mortalities were achieved by C. orientalis and R. officinalis, respectively. The results indicated that both essential oils had a potential in controlling CPB.