Abstract: A 45-day feeding trial was conducted to study the effects of Safmannan as feed additive for African catfish (Clarias gariepinus, Burchell) fingerlings. Total of 270 catfish fingerlings were randomly distributed into nine experimental aquaria. Three complete diets were used in this study: Diet 1, feed from company A (control); Diet 2, feed from company B; Diet 3, feed from company B supplemented with Safmannan. Each of the diets was fed to triplicate groups of fish. The results showed that fish growth was not significantly (p>0.05) affected by diets, even with the supplementation of Safmannan. The feed conversion ratio of catfish fed with Diet 1 was significantly (p<0.05) lower than those fed with Diet 2 but not significantly different from catfish fed with Diet 3, reflecting the competitiveness of Safmannansupplemented feed to the control feed. Fillet of catfish fed with Diet 2 had significantly higher crude protein content than those fed other two diets while significantly lower crude lipid content was resulted in the fillet of catfish fed with Diet 2 and Diet 3. Interestingly, Safmannan supplementation significantly lowered the colony forming unit count and increased serum lysozyme activity. In conclusion, Safmannan could be used as an immunostimulant for catfish farming.