This study investigated the effects of myo‐inositol (MI) on the growth and antioxidant capacity of carp enterocytes. The enterocytes were incubated in media containing 0, 15, 30, 45, 60 and 75 mg MI L−1 for 96 h. The results indicated that MI could increase cell viability. In addition, the activities of cellular alkaline phosphatase (AKP), gamma‐glutamyl transpeptidase (γ‐GT), Na+, K+‐adenosine trisphosphatase (Na+, K+‐ATPase) and creatinkinase (CK) increased with MI supplementation at levels ranging from 15 to 60 mg MI L−1 medium, indicating an improvement in cell differentiation and function. Further, enzymatic antioxidant ability, as measured by total superoxide dismutase (T‐SOD), Cu/Zn‐SOD, Mn‐SOD, catalase (CAT), glutathione peroxidase (GPx) and glutathione‐S‐transferase (GST) activities, improved with MI supplementation. Finally, cell damage, as indicated by lactic acid dehydrogenase (LDH) activity, malondialdehyde (MDA) content of the medium and cellular protein carbonyls (PC), was all depressed by MI. Correlation analyses showed that cell viability (MTT) was positively related to the antioxidant enzyme activities, but negatively related to cell damage (LDH, MDA and PC). In summary, the data showed that MI could improve the growth of fish enterocytes. This result may be partly due to the enhanced antioxidant status and depressed oxidative damage.