Objective To explore the relationship between sex hormone-binding globulin (SHBG) of gestational diabetes mellitus ( GDM ) pregnant women with well-controlled glucose and pregnancy outcomes. Methods Two hundred and fifty-one GDM pregnant women of 24 - 28 weeks in Shengjing Hospital of China Medical University were recruited from Mar. 2005 to Mar. 2010. Two hundred and sixteen cases of GDM with well-controlled glucose were defined as glycemic satisfied group, and they were treated by diet therapy ( 169 cases) or insulin therapy (47 cases) . Thirty-five cases with unsatisfied glucose were defined as glycemic unsatisfied group. One hundred and ninety-two healthy pregnant women of 24 - 28 weeks were defined as healthy control group. Serum SHBG and homeostasis model analysis of insulin resistance ( HOMA-IR) at 24 - 28 weeks and above 36 weeks were measured. GDM was diagnosed bytwo-step method according to the National Diabetes Data Group ( NDDG) criteria. The pregnancy outcomes and complications of the three groups were recorded. Results ( 1 ) Comparison of pregnancy outcomes and complications: glycemic satisfied group was less likely to develop hypertensive disorders in pregnancy ( 10. 6% ) , premature birth(8. 3% ) ,large for gestational age ( LGA) (8. 8% ) , neonatal asphyxia(3. 7% ) and neonatal hypoglycemia ( 2. 3% ) compared to glycemic unsatisfied group ( 42. 9% , 34. 3% , 31. 4% , 22. 9% and 11. 4% ,respectively). And the difference was statistically significant (P ＜0. 05 or P ＜0. 01). There was no significant difference for incidence of polyhydramnios, pueperal infection, postpartum hemorrhage, neonatal hyperbilirubinemia between the two groups ( P＞ 0. 05 ) . When compared to healthy control group(7. 3% ,2. 1% ,4. 2% ,2. 1% and 1. 6% ) ,no significant difference was found for incidence of premature birth( 8. 3% ) , pueperal infection ( 3. 2% ) , postpartum hemorrhage (5. 1% ) , neonatal asphyxia (3. 7% )and neonatal hypoglycemia(2. 3% ,P ＞0. 05). (2) Comparison of results of 24 - 28 weeks and above 36 weeks: serum SHBG of glycemic satisfied group [( 384 ± 88 ) , (457 ± 48 ) nmol/L]was significantly higher than that of glycemic unsatisfied group[(313 ±45) ,(401 ±73) nmol/L];HOMA-IR of glycemic satisfied group (5. 3 ±1.1,5.5 ±1.1) was significantly lower than that of glycemic unsatisfied group (7. 0 ± 1. 3 ,7. 6 ± 1. 7 ; P ＜ 0. 01). Serum SHBG of glycemic satisfied group was significantly lower than that of healthy control group [( 492 ± 95 ) , (565 ± 40 ) nmol/L]; and HOMA-IR of glycemic satisfied group(5. 3 ± 1. 1,5. 5 ± 1. 1) was significantly higher than that of healthy control group (3. 6 ±0. 6,3. 9 ± 0. 5 ;P ＜ 0. 01 ) . FPG of glycemic satisfied group [( 5. 84 ± 0. 28 ) , ( 5. 16 ± 0. 13 ) mmol/L]was significantly lower than that of glycemic unsatisfied group [(6. 13 ± 0. 16 ) , ( 5. 68 ± 1. 14) mmol/L; P ＜ 0. 01]. FINS of glycemic satisfied group [( 20. 4 ± 2. 1 ) , ( 24. 1 ± 4. 2 ) mmol/L]was significantly lower than that of glycemic unsatisfied group [(24. 7 ± 4. 5 ) , ( 29. 9 ± 2. 7 ) mmol/L; P ＜ 0. 01]. ( 3 ) Correlation analysis. Between 24 - 28 weeks, SHBG was negatively correlated with HOMA-IR in the three groups ( r = -0. 952, P ＜0. 01) ; and SHBG was negatively correlated with HOMA-IR in glycemic satisfied group ( r = -0. 903, P ＜0. 01). Conclusions Well-controlled glucose can not completely improve maternal and fetal outcomes of GDM pregnant women. High insulin resistance and low serum SHBG can influence pregnancy outcomes.