The aim of this study was to evaluate the effect of dietary vitamin C supplementation on the blood and biometric parameters of striped bass Morone saxatilis (Walbaum, 1752). For the trial, two groups fed for sixty days were used: group A (basic feed with low vitamin C concentration) and group B (high vitamin C supplement feed). Twenty fish from each group were selected and blood samples were collected to analyse the following blood parameters: white blood cell (WBC), red blood cell (RBC), haemoglobin concentration (Hb), haematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), thrombocytes (TC), albumin (ALB), total bilirubin (TBIL), aspartate aminotransferase (AST); alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), gamma-glutamyl transferase (GGT), lactate dehydrogenase (LDH), chlorine (Cl), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), phosphorus (P), creatinine (CREA) and urea. For all fish, weight, total length and condition factor (K) were registered. Unpaired t-test showed significant differences in biometric indices and some blood parameters between the two groups. Vitamin C supplement improves fish growth and influences important blood parameters that indicate the health status of fish. These results are useful for food management in aquaculture systems of striped bass.