ABSTRACT. – This study aims to assess the age and growth rates of the common carp, Cyprinus carpio (L., 1758) in Sidi Saad Reservoir in Tunisia. Sampling was conducted throughout the entire year of the experiment (January through December). A total of 2285 specimens, ranging from 12 to 58 cm in length (TL) and 24.7 to 2620 g in weight, were caught during the study period. The sample consisted of 1291 females and 994 males with total length weight (W) relationship estimated at W = 0.0156 × TL^2.93. The monthly percentage of specimen having a terminal translucent zone indicated that circuli formed once a year, during the cold season (January). The back calculation method demonstrated the validity of using scales in the estimation of this species’ age and growth. The parameters of Von Bertalanffy growth, based on the analysis of scales for 570 specimens, were estimated for each sex separately: L_∞ = 62.20 cm, K = 0.151 a^–1, t₀ = –0.966 for females, as L_∞ = 57.98 cm, K = 0.165 a^–1, t₀ = –0.873 for males and as L_∞ = 60.05 cm, K = 0.157 a^–1, t₀ = –0.92 for combined sexes. Ten age groups were identified within the common carp population in the studied reservoir.