An experiment was conducted to evaluate the effect of different stocking densities on the growth and survival of Clarias macrocephalus larvae reared in a recirculating aquaculture system for 42 days. Two days old larvae (0.0036 ± 0.0002 g) were reared at four different stocking densities of 10, 20, 30 and 40 ind./liter. Each treatment had three replicates. In first 10 days of the experiment, the larvae were fed exclusively on Moina without operating the recirculating aquaculture system. From the following days, the recirculating aquaculture system was operated continuously and the larvae were fed on commercial feed (42% protein). The results showed that stocking densities had affected the survival rate and growth performance of the larvae during the experimental period. The survival rates of larvae were significantly different among treatments (P0.05) between treatment of 30 and 40 ind./L. The present study was also found that particular developmental stage, nutrient characteristic, changing of food source, size difference and cannibalism might be factors that influences mortality of larvae. Larvae reared at low stocking density showed significantly higher growth performance ...