Objective To analyze iodine nutrition and its correlation with thyroid function in pregnant women.Methods A total of 295 pregnant women were enrolled from Jun.to Oct.2016,and detected for serum levels of thyroid stimulating hormone(TSH),free thyroxine(FT4) and thyroid-peroxidase antibody(TPOAb) by using electrochemiluminescence analysis,and for urinary iodine concentration(UIC) by cold digestion method according to iodine catalytic effect of arsenic-cerium.Results The median of UIC was 174.90 μg/L.The prevalence of iodine deficiency and iodine excess were 40.00% and 7.12% respectively.The prevalence of TPOAb positivity and thyroid dysfunction in the iodine deficiency group and iodine excess group were significantly higher than those of iodine proper group(P<0.05).The levels of TSH and FT4 of iodine excess group were significantly higher than those of iodine proper group(P<0.05).Conclusion The abnormality of iodine nutrition could be common in pregnant women.Monitoring of UIC and thyroid hormones should be highlighted.