What is already known on this topic? Low folate status in pregnancy has been associated with multiple adverse pregnancy outcomes, including neural tube defects, congenital heart defects, fetal growth restriction, low birth weight, and preterm delivery. Low folate status is common in China, especially in northern areas. What is added by this report? Folate status remains suboptimal among pregnant Chinese women in 2015. The median serum folate concentrations of pregnant women were 8.02 ng/mL in China. Low folate status was widespread, especially in rural aeras (9.88 ng/mL) and in northern China Folate concentration was in widespread rural area (9.88 ng/mL) and especially in the northern of China (9.10 ng/mL). Pregnant women in the last trimester had the lowest folic acid concentration (9.18 ng/mL). Taking folic acid supplements every day would achieve adequate serum folate concentrations (10.87 ng/mL vs. 10.11 ng/mL vs. 9.38 ng/mL, P<0.001). What are the implications for public health practice? Folic acid interventions should be strengthened, especially for pregnant women in rural areas and in northern China, those under 25 years old, those with junior school or below education, those pregnant during spring and winter, those overweight and obese, or those with late pregnancy.