Abstract: Objective To investigate the levels of galectin 1 (Gal-1) and galectin 9 (Gal-9) in the serum and placenta of patients with preeclampsia and their clinical significance. Methods A total of 30 pregnant women with early-onset preeclampsia who were admitted to Northern Jiangsu People's Hospital from November 2022 to August 2023 were selected as an early-onset preeclampsia group. Meanwhile, 50 pregnant women with late-onset preeclampsia were selected as a late-onset preeclampsia group. Also, 40 healthy pregnant women who had obstetric checkups in our hospital during the same period were selected as a control group. The levels of serum Gal-1 and Gal-9 in each group were detected by enzyme-linked immunosorbent assay. Immunohistochemistry was used to detect the positive expression rate of placental Gal-1 and Gal-9 in each group. Results The early-onset PE group and the late-onset PE group showed higher serum Gal-1 and Gal-9 levels than the control group (P<0.05), where increased Gal-1 and Gal-9 levels were seen in the early-onset PE group, compared with those in the late-onset PE group (P<0.05). The early-onset PE group and late-onset PE group showed higher placental Gal-1 and Gal-9 positive expression rates than the control group (P<0.05), where increased placental Gal-1 and Gal-9 positive expressian rates were seen in the early-onset PE group, compared with those in the late-onset PE group (P<0.05). Conclusions The levels of Gal-1 and Gal-9 in the serum and placenta of pregnant women with preeclampsia significantly increase, where the early-onset preeclampsia group showed higher levels of Gal-1 and Gal-9 than the late-onset group. These findings suggest that they may be jointly involved in the pathological process of preeclampsia.