Objectives: To investigate the difference of Chemerin expression in maternal blood, umbilical cord blood and placenta in normal pregnant women and women with gestational diabetes and its clinical significance. Methods: Twenty cases of normal pregnant women and twenty cases of women with gestational diabetes were enrolled from Shanghai Jiaotong University Affiliated First People's Hospital from October 2010 to October 2011. The level of Chemerin was detected by ELISA in maternal peripheral blood and umbilical cord blood, its expression in the placenta was determined by Western blot, and the clinical relevance was then analyzed. Results: There was no significant difference in Chemerin expression in maternal peripheral blood between normal pregnancy and gestational diabetes. However, there was significant difference in umbilical cord blood and placenta (p < 0.05), and it was positively correlated with fasting blood glucose, 2-hour postprandial glucose, fasting insulin, insulin resistance index, C-reactive protein, insulin dosage (p < 0.05). Conclusion: Chemerin is an independent influential factor for gestational diabetes. It is highly expressed in umbilical cord blood and placenta of pregnant women with gestational diabetes, and its expression was increased with the dose increase of insulin. It plays an important role in the development of gestational diabetes through regulating glucose metabolism and inflammation.