The purpose of this study was to test the hypothesis that plasma levels of adiponectin can predict angiographic in-stent restenosis after coronary stenting. We prospectively examined adiponectin levels in 127 consecutive patients undergoing elective coronary stenting. Restenosis was defined as more than 50% stenosis at follow-up study by quantitative coronary angiography. There were no significant differences in the clinical characteristics or angiographical findings between the groups with restenosis and no restenosis. The levels of adiponectin did not differ between the restenosis group and the no restenosis group (5.7 +/- 2.8 vs 5.9 +/- 3.6 microg/mL, p = 0.72). The plasma levels of adiponectin were not related with the late loss index after coronary stenting (r = 0.01, p = 0.89). The levels of adiponectin were significantly lower in men than in women (5.5 +/- 3.2 vs 8.8 +/- 3.7 microg/ mL, p < 0.001), and negatively correlated with body mass index (r = -0.21, p = 0.01). We analyzed adiponectin levels in male, female, obese, non-obese, diabetes, and non-diabetes patients, however, there were no significant differences between the restenosis group and no restenosis group. This study has demonstrated that the measurement of adiponectin could not predict angiographic restenosis after elective coronary stenting, whereas the plasma levels of adiponectin were associated with some coronary risk factors in patients with coronary artery disease.