This study aimed to determine the relationship between the adult population and damage rate of Cherry fruit fly, Rhagoletis cerasi L. (Diptera: Tephritidae) harmful on growing cherry in Erzincan province in 2017 and 2018. The main materials of this study were the adult and preadult periods of R. cerasi. Attractive Rebell traps with ammonia salt, stereomicroscope, lancet, etc., were also used. The studies were carried out in 10 orchards, including 5 orchards in Erzincan Central district and 5 orchards in Üzümlü district. According to the results of the study, it was determined that there was a relationship between the adult population and damage rate of Cherry fruit fly. There was a weak or a medium positive correlation (r = 0.457-0.548), and a linear relationship between total adult population density and average damage rate was found in both years.