Background: Preeclampsia (PE) is a serious complication of pregnancy with hallmarks of incomplete placentation, placental ischemia and endothelial dysfunction. Imbalance between vascular endothelial growth factor (VEGF), placenta growth factor (PlGF) and their receptors play important role in pathophysiology of PE. Objective: This study was aimed to asses PlGF mRNA expression in placenta of women affected with PE. Material and Methods: In this cross-sectional study, expression of PlGF mRNA was evaluated in 26 mild PE cases, 15 severe preeclamptic women and 20 normotensive controls. Patients were sub-classified as early onset PE (9) and late onset (32). After RNA extraction, PlGF expression was quantified with qRT-PCR. Results: The results of PlGF mRNA expression between mild-severe, and early-late onset PE patients showed no statistically significant difference compared with the control group (p=0.661, p=0.205 respectively). Conclusion: Despite we found no distinct differential expression of PlGF mRNA in placental tissue of PE patients compared with control women, but according to decreased level of this angiogenic factor in PE even before clinical onset of the disease, determining molecular mechanisms related to reduced secretion of PlGF into the maternal circulation may be useful for future therapeutics