Aim : to determine reference values of angiogenic factors dynamics in pregnancy for female patients with twins and different types of placentation for early diagnostics and assessment of preeclampsia (PE) severity. Materials and Methods . There was conducted 2020–2021 prospective study enrolling 93 females with twin pregnancy to examine 68 with dichorionic diamniotic (DCDA) twins and 25 with monochorionic diamniotic (MCDA) twins. All patients were divided into 2 groups: group I consisted of 65 women with twin pregnancy without PE, group II included 28 women with twin pregnancy complicated by PE. In blood serum of pregnant women the level of soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF) and their ratio were studied for diagnosing and predicting PE severity at 4 time points of gestation (20.0–23.6 weeks, 24.0–28.6 weeks, 29.0–33.6 weeks, 34.0–36.6 weeks). Results . No significant difference was found in angiogenic factors level and their ratio in pregnant women with uncomplicated DCDA and MCDA twins. Regardless of placentation type, sFlt-1/PlGF ratio in women with twin pregnancy and PE at 24 weeks of gestation was 103.3, by 20-fold exceeding this level than in uncomplicated twin pregnancy. Cut-off values for sFlt-1/PlGF ratio were determined allowing highly reliable to rule out diagnosis PE (sFlt-1/PlGF < 21.85; sensitivity 100 %, specificity 85 %) and to diagnose PE (sFlt-1/PlGF > 49.4; sensitivity 71.1 %, specificity 100 %). The sFlt-1/PlGF ratio was higher in pregnant women with severe PE compared with the moderate degree of the disease throughout pregnancy (р < 0.05). In pregnant women with early PE, the angiogenic factors ratio exceeded the upper threshold value from 24 weeks of gestation, with late PE – from 34.0–36.6 weeks. Significantly higher sFlt-1 level (18359 ± 8656 pg/ml vs. 5526 ± 2808 pg/ml; р < 0.001) and the sFlt-1/PlGF ratio (118,0 ± 65,2 vs. 32,8 ± 18,6; р < 0.03) as well as severe degree of PE were noted in patients with induced twin pregnancy from 24.0–28.6 weeks of gestation compared with spontaneous multiple pregnancy (42,2 and 22,2 % respectively; p < 0,05). Conclusion . The developed reference values of the sFlt-1/PlGF ratio in pregnant women with twins and different types of placentation can be used not only to diagnose PE, but also to assess the severity and timing of the disease manifestation.