The study was conducted to investigate the effect of citric acid (CA) supplemented Moringa oleifera leaf meal (MOLM) based diets on hematological indices, nutrient digestibility and growth performance of Catla catla fingerlings. MOLM based diet was sub-divided into one control diet (0% CA) and five test diets, each supplemented with 1%, 2%, 3%, 4% and 5% CA, respectively. Chromic oxide as an inert marker was added in the diets to determine nutrient digestibility. The fingerlings were fed twice daily at the rate of 5 % of live wet body weight on their respective diets. Supplementation of CA in MOLM based diets significantly (p< 0.05) enhanced nutrient digestibility and growth performance of fingerlings as compared to control diet. Highest digestibility of crude protein (68.57%) was observed at 4% CA level, whereas highest digestibility of crude fat (72.23%) and gross energy (66.63%) was observed at 3% CA level. Fingerlings also showed maximum weight gain (WG), weight gain% (WG%), specific growth rate (SGR) and lower FCR value at 3% CA level. Hematological indices of fingerlings fed CA supplemented MOLM based diets were significantly (p< 0.05) improved as compared to control diet. Maximum number of RBC (2.98×106mm-3), WBC (7.91×103mm-3), PLT (66.59) and Hb (8.89 g/100ml), blood PCV (25.25%), MCHC (34.91%), MCH (55.88 pg) and MCV (187.67fl) were also found at 3% CA level. In conclusion CA at 3% level can be supplemented in MOLM based diet for improvement in nutrient digestibility, growth performance and hematological indices of C. catla fingerlings.