Pistachio dieback is a serious disease in Rafsanjan (Iran) farms caused by Paecilomyces variotii. The aim of the present study was to investigate fungicidal effects of essential oil of cloves on Paecilomyces variotii agent of pistachio dieback. In order to evaluate the antifungal properties of Syzygium aromaticum, essential oil from leaf and bud of clove were obtained from hydrodistillation. The isolates were cultured in sabouraud dextrose agar for 48 h at 25°C. The concentration of 100, 200 and 400 ppm of