A total of 108 subjects were enrolled in this study, including 21 healthy subjects(control group), 34 non-obese patients with polycystic ovary syndrome [PCOS1 group, body mass index(BMI)<25 kg/m²], 32 obese patients with PCOS(PCOS2 group, BMI≥25 kg/m²), and 21 simple obese patients whose age and BMI matched with PCOS2(OB group). BMI, waist-hip ratio(WHR), fasting plasma glucose(FPG), postprandial 2h plasma glucose(2hPG), HbA_1C, fasting insulin(FINS), postprandial 2h insulin(2hINS), sex hormones, and lipid parameters were determined. The status of insulin resistance was assessed by homeostasis model assessment for insulin resistant index(HOMA-IR)and insulin sensitivity index(ISI). Levels of plasma galectin-3 and interleukin-6(IL-6)were detected by ELISA. The results showed that the plasma level of galectin-3 was significantly higher in PCOS group than those in control and OB groups(all P<0.05). Moreover, the level of galectin-3 was also higher in OB group compared with control group, while galectin-3 level in PCOS2 group was higher than that in PCOS1 group(all P<0.05). After adjusted by age, BMI, and WHR, correlation analysis showed that the level of galectin-3 was positively correlated with FPG, 2hPG, FINS, HOMA-IR, highly-sensitive C-reactive protein, and IL-6, while negatively correlated with ISI. A multiple linear regression analysis revealed that the plasma galectin-3 concentration was independently associated with IL-6, HOMA-IR, and BMI(all P<0.05). These data suggest that plasma galectin-3 is closely associated with glucose metabolism, chronic inflammation, and insulin resistance, which may be involved in the pathogenesis of PCOS. (Chin J Endocrinol Metab, 2018, 34: 578-582)