To investigate the relationship between inflammatory factors, including C-reactive protein(CRP), tumor necrosis factor alpha (TNF-α), adiponectin, leptin and gestational diabetes mellitus (GDM) and their changes in puerperium. From June 2008 to May 2010, 40 cases with gestational diabetes mellitus, 40 cases of normal pregnancy were enrolled in this study. Fasting venous blood were obtained at early pregnancy (10 - 12 weeks), late pregnancy (36 - 38 weeks) and day 3 and 42 of postpartum. Serumal adiponectin, leptin and TNF-α were measured by ELISA, and serumal CRP were measured by particle enhanced immunoturbidimetric method. The levels of those 4 cytokines and homeostasis model assessment insulin resistance (HOMA-IR) index were compared between two groups. And the changes of 4 cytokines were calculated in puerperium. The receiver operating characteristic (ROC) for TNF-α predicting GDM was designed. (1) The relationship between cytokines and HOMA-IR: the levels of adiponectin of (5.7 ± 1.8) mg/L in the GDM group were significantly lower than (8.1 ± 2.7) mg/L in control group in early pregnancy, and the level of adiponectin was negatively correlated with HOMA-IR (r = -0.333, P < 0.05). The levels of (28 ± 10) μg/L of leptin, (10.0 ± 3.4) ng/L of TNF-α and (4.7 ± 1.1) mg/L of CRP in GDM group were significantly higher than (20 ± 8) μg/L of leptin, (4.6 ± 2.7) ng/L of TNF-α, (2.4 ± 1.2) mg/L of CRP in control group, which were positively correlated with HOMA-IR (r = 0.411, 0.529, 0.308, all P < 0.05). In late pregnancy, the level of adiponectin (3.9 ± 2.2) mg/L in the GDM group was significantly lower than (6.6 ± 2.7) mg/L in control group, and the level of adiponectin was negatively correlated with HOMA-IR (r = -0.344, P < 0.05). The levels of (37 ± 13) μg/L of leptin, (12.7 ± 2.6) ng/L of TNF-α and (6.7 ± 3.6) mg/L of CRP in the GDM group were significantly higher than (30 ± 13) μg/L of leptin, (5.8 ± 2.1) ng/L of TNF-α, (4.4 ± 3.1) mg/L of CRP in control group, which were positively correlated with HOMA-IR (r = 0.414, 0.487, 0.285, all P < 0.05). Multiple linear regression analysis showed that the level of TNF-α at early and late pregnancy was most correlated with HOMA-IR (r = 0.390, 0.284, all P < 0.05). (2) The level of the cytokines and HOMA-IR in puerperium: at day 3 of postpartum, the level of adiponectin of (3.3 ± 1.1) mg/L in the GDM group was significantly lower than (6.2 ± 1.5) mg/L in control group, which was negatively correlated with HOMA-IR (r = -0.283, P < 0.05). The levels of (31 ± 13) μg/L of leptin, (10.1 ± 5.7) ng/L of TNF-α and (35.1 ± 6.5) mg/L of CRP in the GDM group were significantly higher than (21 ± 15) μg/L of leptin, (5.6 ± 3.0) ng/L of TNF-α, (30.5 ± 8.5) mg/L of CRP in control group. And leptin and TNF-α levels were positively correlated with HOMA-IR (r = 0.372, 0.494, all P < 0.05). At day 42 of postpartum, the level of adiponectin in GDM group was negatively correlated with HOMA-IR (r = -0.299, P < 0.05), and the levels of leptin and TNF-α were positively correlated with HOMA-IR (r = 0.401, 0.442, all P < 0.05). Multiple linear regression analysis showed that the level of TNF-α at day 3 and day 42 was most correlated with HOMA-IR (r = 0.363, 0.274, all P < 0.05). (3) ROC analysis of data from early pregnancy showed that the threshold for TNF-α to predict GDM was 5.45 ng/L. TNF-α might be the index to predict GDM and evaluate prognosis.