Abstract: In this study, the effect of cold treatment to Mediterranean fruit fly and cherry fruit fly on the cherry fruits in the storage conditions has been examined. In the climate chamber, mass-reared Mediterranean fruit fly has been used to artificially infest to the cherry fruits; while for the cherry fruit fly, naturally infested cherry fruits have been used. The tests have been made at 0.5 ± 0.5 °C and 85 ± 5% relative humidity conditions in the cold storage room, which has TS EN ISO 9002 Quality System Certificate. Egg and third instar-larvae which are the most resistant instars of the Mediterranean fruit fly have been used in the tests. Larva tests have been made on 80,000 individuals in total, and egg tests have been made on 60,000 individuals. In the same storage conditions cherry fruit fly tests have been made on 11,000 fruits in total and on 880 larvae. As a control character; cherry fruits have been infested with 5,450 larvae and 5,450 eggs, and the progress has been observed at 25 ± 1 °C. During the tests, fruit flesh temperature has been measured and postharvest quality has been evaluated. As a result of these tests, it was concluded that cold treatment of 20 and 12 days at 0.5 ± 0.5 °C and 85 ± 5% relative humidity killed 100% of cherry fruit fly and Mediterranean fruit fly in the cherry fruits, respectively.