This research aimed to see how effectively chromium nanoparticles (Cr-NPs) improve minerals absorption and carcass composition in Catla catla fingerlings given sunflower meal based diets. In a 90-day experimental design, seven test diets were supplemented with graded levels of nano-Cr (0, 0.5, 1, 1.5, 2, 2.5, and 3 mg kg−1) and 15 fingerlings (initial weight; 6.83 ± 0.077 g) were kept in triplicate (25–28 °C). Feed was provided to fingerlings at the rate of 5% of their wet weight and fed twice a day. As an inert marker, chromic oxide was used. The highest effectiveness in minerals absorption (Ca, Na, K, Cu, Fe, Mn, P, Cr, Mg, Zn and Al) was observed at 2 mg kg−1 Cr-NPs supplementation. These levels were statistically more significant (p