To explore the value the levels of pregnancy-associated plasma protein-A (PAPP-A), vascular endothelial growth factor (VEGF), alpha-fetoprotein (AFP), and free estriol (uE3) for dignosing the women with preeclampsia, and to study its correlation. Methods: 78 pregnant women with preeclampsia were selected in study group from January 2017 to July 2018, and 50 healthy pregnant women were selected in control group during the same period. The levels of serum PAPP-A, AFP, uE3 and VEGF, and their correlation were analyzed. Results: The levels of serum PAPP-A, AFP, uE3, and VEGF of women in the study group were significant lower than those of women in the control group, and those of women with severe preeclampsia were significant lower than those of women with mild preeclampsia (P<0.05). The serum levels of PAPP-A, AFP, and uE3 of women with early-onset severe preeclampsia were significant lower than those of women with mild preeclampsia were significant higher than those of women with late-onset severe preeclampsia, but the serum VEGF level of women with early-onset severe preeclampsia was significant lower (all P<0.05). The level of PAPP-A of women with preeclampsia was positively correlated with their AFP level, uE3 level, or VEGF level (P<0.05).Conclusion: Serum PAPP-A, AFP, uE3, and VEGF of pregnant women are involved in the occurrence and development of preeclampsia, which can be used as an auxiliary examination index for clinical screening of preeclampsia, and have positive significance for clinical diagnosing and evaluating the prognosis of preeclampsia.