his study aimed to evaluate the effects of dietary supplementation with nano-curcumin (NCur) and a nano-curcumin/chitosan blend (NCur/Ch) on growth performance, digestibility, immune response, antioxidant status, intestinal morphometric characters, and gene regulation in Nile tilapia. Fish ( n = 180, initial body weight = 12.0 ± 0.53 g) received supplementary NCur at rates of 0 (control), 0.00625, and 0.0125, and NCur/Ch at rates of 0.00625 + 0.5 g/kg diet for 4 weeks. Growth performance parameters (final weight and length, body mass gain, specific growth, and length gain rates) were markedly increased, and the feed conversion ratio was significantly decreased in the NCur- and NCur/Ch-supplemented groups. Digestive enzyme (amylase), immune response markers (immunoglobulin M, nitrous oxide, and lysozyme activity), plasma albumin, and total protein were increased significantly, mainly with a diet supplemented with 0.00625 g NCur/kg. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), glucose, and cortisol levels decreased in the supplemented groups compared to the control. S