Leptin has been focused on one of the key elements showing anti-obese effects. Diet-induce obese (DIO) C57BL/6 male mouse model fed with high-fat chow was developed to study correlation between levels of blood leptin level compared with standard and fat group. Leptin level has been calculated with screen-printed gold electrode (SCGE) coated with immobilized monoclonal anti-leptin antibody. Antibody was immobilized by chemical linker established by 4-MBA (4-mercaptobenzoic acid) coated on gold surface of SCGE. Leptin level was measured by two electrochemical analytic methods; electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). DIO group represented significant physical values (body weight, height, waist circumference and fat, organ masses) and notable electrochemical signals from EIS and CV. Our results suggest that it can be demonstrated different types of real human serum samples.