Visfatin is expressed in visceral adipose tissue and is up regulated in some animal models of obesity. Insulin-mimetic actions of visfatin may be part of the feedback regulation of glucose homeostasis, so plasma glucose or insulin may have effect on visfatin levels in humans. The aim of study was to investigate plasma glucose, insulin and visfatin during oral glucose tolerance test (OGTT, 75 gr) in obese women. 22 obese women (age: 36.73±1.88 yrs; BMI 34.72±0.67 kg/m2) were studied. Plasma visfatin (EIA Phoenix, ng/ml), adiponectin and leptin (Linco RIA, ng/ml), insulin (RIA Inep, mU/l) and glucose (mmol/l) were measured in basal state, while additional visfatin and insulin were measured at the peak glucose during OGTT. Insulin sensitivity (M index:mg/kgBW/min) was measured using euglycemic 2 hr clamp. Basal glucose was 4.78±0.10 and peak glucose during OGTT 8.20±0.42 (P<0.005). There were no significant differences in visfatin between basal sample and at the peak glucose levels (72.26±3.34 vs. 79.46±7.15, P>0.05). Basal insulin was 16.57±1.28 and at the peak glucose 97.88±13.01 (P<0.05). After analysis of the individual data we found that 7 obese women (Group A) had significant decrease (44.77±3.87 vs.36.19±8.42, P<0.05) and 15 women (Group B) had significant increase in visfatin during OGTT (69.85±4.49 vs. 99.66±2.59, P<0.05). There were no significant difference between Group A and B in BMI (34.85±1.12 vs. 34.65±0.87), age (36.00±4.64 vs. 37.07±1.81), basal glucose (4.91±0.26 vs. 4.73±0.09), basal insulin (14.73±1.82 vs. 17.43±1.67), adiponectin (5.90±3.19 vs. 10.97±2.94), leptin (34.66±6.34 vs. 33.09±3.45), peak glucose (8.96±1.10 vs. 7.85±0.36), insulin at peak glucose (80.54±20.78 vs. 105.97±16.46) neither in insulin sensitivity (5.51±0.87 vs. 4.81±0.64). Our data demonstrate existence of two type of visfatin response during OGTT in obese women. It is still not clear which influence determines different type of visfatin response during OGTT and further studies are necessary to elucidate these mechanisms.