Background: Demodex mites can cause ocular demodicosis in humans. Natural products such as tea tree oil are used for ocular demodicosis, which can take a long time to treat. The aim of our study is to investigate the effects of some essential oils on in vitro mite lifespan. Methods: Eyelashes were examined under a light microscope. Mites were determined and the killing times of mineral oil, tea tree oil, black seed oil, St. John's Wort oil, sage oil and thyme oil were recorded. The active ingredients of thyme, tea tree and sage oils were determined by GC / MS method.Results: It was determined that 1% concentration of thyme oil has more effective killing time than 5% concentrations of tea tree oil and sage oil (p <0.0001). The most important active ingredients were carvacrol in thyme oil, terpinen-4-ol in tea tree oil, and 1.8-cineol in sage oil. Conclusion: Thyme oil was the most effective oil in killing mites. In addition, the first steps were taken that thyme oil and its products can be used in therapy.