Abstract： Objective To investigate the prevalence of iron deficiency(ID)and iron deficiency anemia (IDA) in pregnant women in urban areas of China. Methods The study was a national cross-sectional survey conducted from September 19th, 2016 to November 20th, 2016. According to the classification of the National Bureau of Statistics, all survey sites were set up in 6 regions of the country. Pregnant women were continuously selected using multistage stratified sampling. A total of 12 403 pregnant women were collected and examined for serum ferritin and hemoglobin levels. Results The median serum ferritin level during pregnancy was 20.60 μg/L(11.78-36.98 μg/L), the hemoglobin level was(118±12)g/L. With the progress of pregnancy, the levels of serum ferritin and hemoglobin decreased gradually. The median serum ferritin levels in the first, second trimester and third trimester were 54.30 μg/L(34.48-94.01 μg/L), 28.60 μg/L(16.40-50.52 μg/L), and 16.70 μg/L(10.20-27.00 μg/L)respectively(P<0.01). The mean hemoglobin levels were(127 ± 10)g/L,(119 ± 11)g/L and(117 ± 11)g/L respectively(P<0.01). The prevalence of ID in urban pregnant women was 48.16%(5 973/12 403), and IDA prevalence was 13.87% (1 720/12 403). The prevalence of IDA in the first, second trimester and third trimester were 1.96% (20/1 019), 8.40%(293/3 487)and 17.82%(1 407/7 897), respectively(P<0.01). The prevalence of standardized ID and IDA were significantly different in various regions of China(P<0.01). The standardized prevalence of ID were relatively higher in East China and Northeast China, 57.37% and 53.41% respectively, while it was the lowest in Southwest China, 30.51%. The standardized prevalence of IDA in South Central, Northwest, and East China were relatively high, 21.30%, 16.97% and 17.53% respectively, and the standardized prevalence of IDA in Southwest China was the lowest, 5.44%,the differents in various regions were significant(all P<0.01). Conclusion The current phenomenon of ID and IDA in pregnant women is still very common,and nutrition and health care during pregnancy should be strengthened.