This study aimed to evaluate the effect of replacing fish meal in the fish diet by zooplankton meal on the growth performance of European sea bass, Dicentrarchus labrax. A total of 900 fingerlings of the D. labrax were collected from fish hatchery Kilo 21, Alexandria and transported to the fish rearing unit in El-Max Research Station, National Institute of Oceanography and Fishers (NIOF), Alexandria, Egypt. After two weeks for acclimation, the fish were divided into 5 groups, 3 replicates for each group (60 fish in one cubic meter of Haba for each replicate). The five experimental diets were: G₁: commercial diet (control group); G₂, G₃, G₄, and G₅ fish meal in this commercial diet was replaced by zooplankton meal as 25%, 50%, 75% and 100%, respectively. The highest values of growth performance parameters and PER & FER of D. labrax were recorded in G₅, while the lowest values were recorded in the control group. The best average of FCR (1.75±0.02) was recorded for G₅ and its bad average (2.18±0.18) was recorded in G₁. The present study concluded that zooplankton positively affected growth performance parameters and enhanced feed utilization of sea bass.