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Box tree moth, Cydalima perspectalis (Walker, 1859), is one of the major destructive pests that feed on the leaves and shoots of various Buxus species. In the course of this survey, the life cycle of C. perspectalis was studied in laboratory and natural (Hyrcanian Forests) conditions. The laboratory experiments were carried out at temperature of 25±1ºC, 70±10% relative humidity and a photo phase of 16 light: 8 dark hours. The average duration of an egg, larva, pre-pupa, pupa, as well as female and male longevity were 5.09±0.04, 23.15±0.17, 1.04±0.02, 7.80±0.05, 15.31±0.73 and 12.92±0.71 days, respectively. As an important pest newly introduced in northern Iran, the Box tree moth completes two and partial third generations per year. The results of this study would be useful for improving pest management strategies.