Age determination and some growth parameters were studied in a population of Rana ridibunda from Yildizli Stream, Trabzon, Turkey by skeletochronology. Age was determined for individual frogs by counting the number of resting lines (RL) in cross-sections taken from phalanges. The maximum longevity of females and males was 6 and 7 years, respectively. The minimum age at maturity was 2, at 55 mm snout-vent length (SVL), for females, and 2, at 46 mm, for males. Males were sexually mature after the third or fourth winter although some females mature after the fifth winter. SVL was ranged from 55 to 99 mm (74.64 +/- 13.37) in females and 38 to 83 mm (64.58 +/- 11.09) in males. Male SVL was significantly correlated with age, but no significant correlation was obtained between female SVL and age. Gonad weights show highly significant correlation with SVL in both sexes but no significant correlation with age.