Abstract：Objective To explore the influencing factors for maternal anemia during the third trimester of pregnancy, so as to provide the evidence for the effective prevention of anemia. Methods Data of parturients, who received prenatal care and delivered at Hangzhou Women＇s Hospital from October to December of 2019 were retrospectively collected and analyzed. The obstetric electronic medical record system of this hospital was used to collect general information of the subjects. Serum ferritin, serum vitamin B12, serum folic acid and hemoglobin were determined at the second and third trimester. A multivariate logistic regression model was used to analyze the influencing factors for anemia in the third trimester. Results A total of 1 143 parturients were enrolled, with a median age of 29 ( interquartile range: 4 ) years. Among them, 1 050 cases had normal weight before pregnancy, accounting for 91.86%; 267 cases were multiparas, accounting for 23.36%; 74 cases of anemia occurred during the third trimester of pregnancy, accounting for 6.92%.Multivariate logistic regression analysis indicated that the multipara（OR=1.714,95%CI: 1.032-2.848）, iron deficiency duiring the second trimester（OR=3.301,95%CI: 1.401-7.781）, iron deficiency during the third trimester （OR=14.134,95%CI: 1.944-102.774）and folate deficiency during the third trimester（OR=2.960,95%CI: 1.295-6.766）were influencing factors for anemia during the third trimester. Conclusion Anemia during the third trimester of pregnancy is related to iron deficiency during the second and third trimesters, folic acid deficiency during the third trimester, and multipara.