This study was conducted to evaluate the effect of adding phytase enzyme in diet on growth performance, nutrient digestibility, and survival rate in fingerlings of P. hypothalamus. Fingerlings of P. hypothalamus with the average weight 1.81 ± 0.06 g per fingerling, used in this study were obtained from Muntilan, Central Java. An experimental randomised complete design was used with 5 treatments and 3 repetitions. The treatments were A (0 FTU kg–1 diet, B (150 FTU kg–1 diet), C (300 FTU kg–1 diet), D (450 FTU kg–1 diet), and E (600 FTU kg–1 diet). The parameters to be determined include specific growth rate (SGR), efficiency of feed utilisation (EFU), protein efficiency ratio (PER), apparent digestibility coefficient protein (ADCP), apparent digestibility coefficient phosphor (ADCF), survival rate (SR) and water quality parameters. The experimental results significantly (P<0.01) affected SGR, EFU, PER, ADCP and ADCF. On the other hand, the had insignificant (P>0.05) effect on SR of P. hypothalamus fingerlings. Based on the results, it is concluded that optimum doses of phytase enzyme in terms of SGR, EFU, PER, ADCP and ADCF in the catfish (P. hypothalamus) are 324, 314, 300, 300 and 300 FTU kg–1 diet respectively.