The aim of this research was to evaluate the fumigant activity of essential oils obtained from aerial parts of three Lamiaceae plants [Mentha longifolia L. subsp. typhoides (Brig.) Harley, Dorystoechas hastata Boiss. & Heldr. ex Bentham (endemic), and Origanum minutiflorum O. Schwarz et. H. Davis (endemic)] which naturally grow in Antalya region on 10-15 days old (2nd or 3rd instar) nymphs of German cockroach (Blattella germanica L.) at different concentrations ranging from 25 to 500 mu l/L. GC-MS analysis revealed the presence of 1,8-cineole (25.9%), borneol (18.98%) and camphor (16.93%) in D. hastata, carvacrol (97.93%) in O. minutiflorum, as well as cis-piperitone epoxide (53.25%) and piperitenone oxide (31.46%) in M. longifolia subsp. typhoides. When all essential oils were compared on the basis of fumigant toxicity, D. hastata essential oil is a more statistically significant fumigant than the other two essential oils at 100, 200 and 300 mu l/L levels. There is no significant difference found at these concentrations between M. longifolia and O. minutiflorum essential oils. Moreover, at application levels of 400 and 500 mu l/L, the most toxic essential oil was also from D. hastata, followed by those of M. longifolia and O. minutiflorum, respectively.