Abstract: Objective To study the changes of placental growth factor (PLGF) levels in pregnant women with hypertensive disorders complicating pregnancy (HDCP) and explore the relationship of serum PLGF levels and disease severity of HDCP. Methods One hundred and thirty pregnant women who were admitted to our hospital for prenatal care from July 2013 to July 2015 were selected. Of the 130 cases, fluorescence immunoassay analyzer was used to detect PLGF level of 100 cases pregnant women with HDCP (40 cases had gestational hypertension, 30 cases had mild preeclampsia, 30 cases had severe preeclampsia) and 30 normal pregnancy women, and the results of these two groups were compared. Results The levels of PLGF in serum of gestational hypertension group, mild preeclampsia group and severe preeclampsia group were (43.33±15.10) ng/L, (20.13±11.21) ng/L, (5.83±2.10) ng/ L, respectively. Compared with control group, the level of PLGF decreased significantly in HDCP group (63.43±26.51) ng/L vs (25.83±22.10) ng/L, P＜ 0.01. Conclusion The 1evels of PLGF in patients with HDCP decrease significantly compared with normal pregnancy women, and it decreases with the severity of the disease.