The aim of this study was to investigate the association of macrophage migration inhibitory factor (MIF) polymorphism rs1007888 with gestational diabetes mellitus (GDM), and its association with postpartum metabolic syndrome. In a case-control study, 147 GDM and 169 healthy pregnant patients were recruited. Blood sample was taken 2 times from all the participants; one at 24-28 weeks of gestation, second at 6-12 weeks of postpartum. Biochemical measurement and DNA extraction were performed. The PCR_SSP was performed for genotyping. The frequencies of AA, AG, and GG genotypes were 11.24% (19), 76.92% (130), and 11.83% (20) in healthy pregnancies and were 7.48% (11), 70.74% (104), and 21.76% (32) in GDM individuals. The distributions of MIF genotypes were significantly different in GDM and healthy subjects (p=0.04). Moreover, GG genotype had a significant association with pre-pregnancy obesity and family history of diabetes. In postpartum follow-up GG genotype was two-fold more frequent in women with metabolic syndrome (p=0.01, odds ratio=2.30, CI 95%; 1.23-4.30) and relative risk was equal 1.77 (CI 95%; 1.19-2.64). Our findings demonstrate an association between MIF polymorphism rs1007888 and susceptibility to GDM in pregnancy and metabolic syndrome development.