Objective To explore the risk factors of twin preeclampsia,so as to provide evidence for early identification,early warning and prognosis,and better guide clinical work.Methods The clinical data of 236 cases of twin pregnancy with preeclampsia and 200 cases of preeclampsia in the same period in Beijing Haidian District maternal and child health care hospital were analyzed retrospectively.The clinical epidemiology of patients in two groups was conducted in a cohort study to analyze the risk of disease,and to explore the risk factors for twin pregnancy and preeclampsia.Results The preeclampsia incidence of multipara (OR =2.275,95％ CI:1.404-3.686) increased compared with the primipara.The risk of preeclampsia increased in elderly patients (≥35 years old) (OR =1.412,95％ CI:0.917-2.174).The preeclampsia incidence of double chorionic twins was 1.946 times that of monochorial twins (OR =1.946,95％ CI:1.321-2.868).The preeclampsia incidence of assisted reproductive technology pregnancy was 2.063 times that of natural pregnant women (OR =1.946,95％ CI:1.321-2.868).Overweight and obesity were closely related to preeclampsia (OR =3.482,95％ CI:2.064-5.874;x2 =23.498,P ＜ 0.001) and excessive weight gain during pregnancy increased the risk of preeclampsia.Conclusions Primipara,advanced age,double chorionic twins,assisted reproductive technology pregnancy,overweight or obesity and excessive weight gain during pregnancy were all risk factors of preeclampsia in twin pregnancy women.Age,chorionicity and assisted reproductive technology were independent risk factors for preeclampsia.In order to reduce the incidence of preeclampsia and improve the prognosis in twin pregnant women,high risk factors should be identified as early as possible and more perinatal health care should be taken in clinical work.