Metabolic dysregulation and obesity are associated with many metabolic alterations, including impairment of insulin sensitivity and dyslipidemia. Recent studies highlight the key role of phosphatidylinositol 3,4,5-triphosphate-dependent Rac exchange proteins (PREX proteins) in the pathogenesis of obesity, advocating further elucidation of their potential therapeutic implications. The present study aimed to estimate the serum level of PREX proteins and its potential association with insulin resistance markers and plasma lipids level in obese and overweight non-diabetic patients. The study included 30 persons classified as obese, 30 as overweight, and 30 healthy individuals of similar age and gender. The levels of PREX1 and PREX2 were measured using ELISA kits, insulin, fasting glucose, glycosylated hemoglobin and total lipid profile were determined using appropriate photometric kits. HOMA-IR was used as a measure of insulin sensitivity. According to the obtained results, obese non-diabetic patients had higher serum PREX1 level compared to both overweight and normal-weight individuals. PREX1 correlated positively with the markers of insulin resistance and dyslipidemia. PREX2 level was shown to be lower both in obese compared to overweight patients and in overweight compared to normal-weight individuals. PREX2 correlated negatively with the markers of insulin resistance but not with the markers of dyslipidemia. Keywords: dyslipidemia, insulin resistance, obesity, overweight, PREX proteins