Abstract A research was conducted to find out the effect of periodic feed restriction on feed utilization including apparent net energy retention; protein productivity value; feed conversion ratio, and on body condition indices including hepatosomatic index and condition factor of humpback grouper, Cromileptes altivelis. Two hundred sixteen fishes, 10.8 g average body weight, were stocked into 18 fiber glass aquaria measuring 40 x 30 x 80 cm, so that there was 12 individuals in each aquarium. The fish was subjected to the following feeding regime: fish subjected to normal feeding daily (P0) as control; repeating cycle of one day feed restriction and two days normal feeding (P1); and repeating cycle of one day feed restriction and three days normal feeding (P2). Such feeding regime was assigned to fish kept in the aquaria according to completely randomized design in six replicates. The experimental fish was fed with trash fish as much as 5 % of body weight in the morning at 0800-0900 and afternoon at 1500-1600. Water quality parameters including pH, temperature, disolved oxygen, salinity was monitored daily. The results indicate that periodic feed restriction affect net energy retention, protein productivity value, feed conversion ratio, hepato somatic index and condition factor of humpback grouper. To conclude, periodic feed deprivation improves feed utilization and body condition indices of humpback grouper, Cromileptes altivelis.