Due to the economic importance of Diplodus vulgaris in Benghazi coast (Libya), this study is concerned to estimate the biological and population parameters required for proposing a future plan to sustain and manage this valuable fish resource. Age estimates ranged between 1+ and 8+ in both methods scale and length frequency distribution methods. The parameters of Von Bertalanffy growth model were estimated for male, female and both sex as L∞ = 37.4 cm, 39.3cm, 33.3 cm, K = 0.17, 0.199, 0.113, to = -1.66, -2.02, -1.6 and φ′ = 2.4, 2.5, 2.1 respectively. The coefficients of total mortality (Z), natural mortality (M) and fishing mortality (F) were 0.3, 0.1 and 0.2 year-1 respectively. The Exploitation rate (E) was 0.7 and survival rate was 0.7.
