In order to find new environment-friendly and easily formulated and accessible insecticides, the essential oils of Pestacia atlantica var. kurdica (Anacardiaceae) were used against the adults of Lasioderma serricorne F. (Col.: Anobiidae) in vitro. Analysis of Pestacia atlantica var. kurdica (Anacardiaceae) essential oil used for insect fumigation by GC Mass analysis revealed the presence of 13 compounds including a-pinene (77.75%), camphene (6.6%), and b-pinene (3.45%). The experiment was conducted in a completely randomized design with six treatments (five various concentrations and one control). The essential oil was prepared by water distillation method with Clevenger Apparatus. Experiment was carried out at 30±2oC and 60±5% R. H. under dark condition. Treatments consisted of five different concentrations of essential oils and a control group. Each concentration consisted of three replicates and each replicate consisted of 20 one to seven- day adult insects. The LC50 for the oil of P. atlantica, in this experiment was 216.67 ml/l airs for L. serricorne. Results showed that essential oils of Pestacia atlantica var. kurdica (Anacardiaceae) had significant fatality on adult pests studied.