The present study was conducted to examine different dietary levels of iron (FeSO4) on some haematological parameters of ship sturgeon, Acipenser nudiventris including red blood cells (RBC), white blood cells (WBCs), differential WBCs, hematocrit (Hct), Hemoglobin (Hb), the mean corpuscular hemoglobin (MCH) and the mean corpuscular hemoglobin concentration (MCHC), the mean corpuscular volume (MCV), immunoglobulin (IgM), ferritin, transferrin and plasma Fe^2+. Four experimental treatments and one control group with three replicates were considered for the experiment. The experimental treatments were fish fed experimental diets containing different levels of FeSO_4 i.e. 100, 200, 250, and 300 mg kg. diet^-1. After 60 days, there were significant differences between experimental groups in terms of WBCs, lymphocytes, neutrophils, monocytes, eosinophils, MCH and MCHC, MCV, total plasma protein, IgM, ferritin, transferrin and plasma Fe^2+ (p〈0.05). In the treatment fed 100 mg. iron kg. diet^-1, more levels of IgM and total plasma protein were observed compared to other experimental groups (p〈0.05). The highest values of neutrophils, monocytes and MCHC were found in control fish whereas MCV, MCH and eosinophils values were higher in the treatment fed 200 mg. iron kg. diet^-1 (p〈0.05). Also, more WBCs were observed in 250 mg. iron kg. diet^-1 treatment than in other groups (p〈0.05). The values of lymphocytes, RBC, Hct, Hb, ferritin, transferrin and plasma Fe^2+ were higher in fish fed 300 mg. iron kg. diet^-1 compared to other experimental groups (p〈0.05). In conclusion, our results showed that the supplementation of ship sturgeon diets with high levels of iron enhances the RBC, Hct, Hb, ferritin, transferrin and plasma iron.