The present study evaluates the use of rubber seed meal (RSM) and its defatted product on the growth and feeding performance of common carp Cyprinus carpio L. Digestibility test using chromium oxide as a tracer showed that defatted RSM (DRSM) resulted in significantly higher total feed, protein, Ca and P digestibility than those of unprocessed RSM (URSM). Growth test was performed with a control and three experimental diets which were 50% DRSM (50% of protein originated from DRSM), 75% DRSM (75% of protein originated from DRSM) and 50% URSM (50% protein originated from URSM). The use of diet containing URSM to replace 50% protein source resulted in the lowest growth and feeding performance which might correlate to the high cyanide content (1.16%) in the diet. Furthermore, providing the fish with this particular experimental diet also caused decline in fish haematological parameters and increased abnormalities in the fish intestine and kidney. Overall results suggested that the use of defatted RSM to replace 50% of other protein sources resulted in a comparable growth and feeding performance of common carp juvenile without any adverse effect.