Serum biochemical parameters are important aspects in the management of endangered species such as Huso huso. The values of these parameters can be used for confirming the sex and any changes in the quality of waters and related soils. Serum samples of 15 H. huso fish were analysed and their serum parameter values were determined as mean±SD in both sexes. Age, weight, total length and fork length were the same between groups. We compared the levels of calcium (Ca; 2.13 ± 0.69–2.37 ± 0.38 mmol/l), total protein (TOP; 4.51 ± 1–5.50 ± 0.94 mg/dl), blood urea nitrogen (BUN; 1.32 ± 0.23–1.35 ± 0.31 mmol/l), albumin (Alb; 0.88 ± 0.18–1.26 ± 0.29 mg/dl), globulin (Glb; 3.63 ± 0.84–4.5 ± 0.69 mg/dl), uric acid (UA; 1.66 ± 0.18–1.79 ± 0.27 mmol/l), creatinine (CREA; 30.48 ± 4.31–30.48 ± 6.10 mmol/l), phosphorous (P; 2.18 ± 0.38–2.91 ± 0.67 mmol/l), magnesium (Mg; 1.15 ± 0.26–1.51 ± 0.35 mmol/l), glucose (Glc; 3.42 ± 0.84–6.69 ± 1.54 mmol/l), alkaline phosphatase (ALP; 4.48 ± 1.82–5 ± 1.04 IU/l) and amylase (156.19 ± 34.07–166.25 ± 64.27-IU/l). We have shown that there were no differences in the Ca, TOP, BUN, UA, CREA, Mg, ALP and amylase between sexes. However, male fish have higher Glc, P, Alb and Glb than females.