Trialeurodes vaporariorum (Westwood) is a polyphagous species. This pest is now well-established in the greenhouse ecosystem and is an economically important pest of horticultural and ornamental crops. The fumigants toxicity of tarragon (Artemisia dracunculus L.) and dill (Anethum graveolens L.) essential oils on the life stages of Trialeurodes vaporariorum were investigated under laboratory conditions. Plants essence samples were obtained from the aerial parts of the plant by using Clevenger device. In this study, six concentrations (5 concentrations and one control) were used to evaluate LC50 level and five time periods were used for LT50. The LC50 values for Artemisia dracunculus and Anethum graveolens at 24 h after treatment of the eggs, nymphs and adults were 1.18, 0.45 and 0.69 μl l-1 air and 12.99, 5.67 and 8.03 μl l-1 air, respectively. Also, the LT50 value of tarragon essential oil on the eggs, nymphs and adults were 15.02, 5.12 and 9.05 hours and for dill were 18.66, 5.51 and 10.14 hours, respectively.