Introduction: Chemerin as a new adipokine has recently been studied for its crucial role in adipocyte differentiation and insulin signaling. In this study, chemerin levels were determined in the serum of pregnant women of the same gestational age with gestational diabetes mellitus (GDM) and compared with those of healthy pregnant women for their impact on the metabolic process and incidence of gestational diabetics. Materials and Methods: After obtaining a written consent of each individual, totally 200 serum samples were collected from the healthy and gestationally diabetic pregnant women groups. In addition to chemerin, other effective biochemical and metabolic factors of carbohydrate and lipid were determined. Leptin content of cord blood was measured in 100 infants from healthy (50) and gestational diabetes (50) groups. Results: Mean serum chemerin levels of pregnant women with gestational diabetes (152.4±46.5 µg/dl) were significantly higher (p<0.001) in comparision with those of non-diabetic pregnant women (128.7±43.7 µg/dl). Serum chemerin levels were significantly associated with metabolic syndrome-related parameters, including body mass index (BMI) (P<0.05), Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) (P<0.001), fasting insulin (P<0.001) and fasting blood (p<0.01) was conducted. Serum chemerin was not significantly correlated with cord blood leptin. Conclusion: Serum chemerin levels were higher in pregnant women with gestational diabetes than their non-diabetic pregnant counterparts. Serum chemerin was also independently associated with markers of insulin resistance, and body mass index. Leptin, biochemical and metabolic parameters of mother’s infants were not correlated between the two groups.