This study was conducted in summer-winter 2012 to determine the longevity, fecundity and developmental period of each stage of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) under natural conditions in Canakkale province, Turkey. During the tomato growing season, T. absoluta completed 5 generations. The generation time changed according to temperature. Longevity was recorded as 3.37-6.14 days in males and 7.7-9.75 days in females. The fecundity was 75.5-138.4 eggs. Developmental period of the eggs ranged between 3.72 and 10.54 days. The larval developmental period was 12.82-26.7 days and the pupal developmental period ranged from 7.52 to 20.62 days. The total number of eggs per female for each generation varied between 31 and 186 and the females laid 68-72% of their eggs in the first five days. Degree days per generation changed between 461.02 DD and 470.94 DD. Biological properties of the pest changed in each generation. In this study, the biological parameters of T. absoluta were determined and this data can be used as an important step towards developing successful Integrated Pest Management strategies.