Objective To explore the incidence and influencing factors of prenatal depression in pregnant women with different parities of pregnancy. Methods A total of 336 pregnant women in the third trimester of pregnancy were selected from the obstetric clinic of Taihe Hospital of Traditional Chinese Medicine in Fuyang from May to October 2020， including 210 first pregnant women and 126 second pregnant women. The general demographic data were assessed with the self-made general information scale. The antenatal depression was assessed with the Edinburgh Postnatal Depression Scale（ EPDS）. Sleep and anxiety were assessed with Pittsburgh Sleep Quality Index（ PSQI） and Self-rating Anxiety Scale（ SAS）. Results The incidence rate of antenatal depression in pregnant women was 31.55%（ 106/336）， and the incidence rate of antenatal depression was higher in first pregnancy than in second pregnancy［ 36.19%（ 76/210） vs 23.81%（ 30/126）， χ2=5.590， P=0.018］. Antenatal anxiety（ OR=5.611，95%CI=2.318-13.582，P＜0.001） and sleep disorders（ OR=1.995， 95%CI=1.019-3.908，P=0.044） were risk factors of antenatal depression in first pregnant women， and prenatal education（ OR=0.267，95%CI=0.137-0.519，P ＜ 0.001） was a protective factor of antenatal depression in first pregnant women； antenatal anxiety（ OR=5.467，95%CI=1.284-23.288，P=0.022） and junior high school education or below（ OR=4.396， 95%CI=1.060-18.223，P=0.041） were risk factors of antenatal depression in second pregnant women. Working during pregnancy（ OR=0.340，95%CI=0.132-0.87，P=0.026） was a protective factor of antenatal depression in second pregnant women. Conclusions The incidence rate of antenatal depression is higher in the third trimester， and the incidence rate of antenatal depression is higher in the first pregnancy than in the second. Sleep disorder， antenatal anxiety and prenatal education were the influencing factors of antenatal depression in the first pregnancy. Antenatal anxiety， education and work status were the influencing factors of antenatal depression in the second pregnancy. The intervention and prevention of antenatal depression in different parity should focus on different risk factors.