Preeclampsia is one of the most important and complexed disorders for women's health. Searching for novel proteins as biomarkers to reveal pathogenesis, proteomic approaches using 2DE has become a valuable tool to understanding of preeclampsia. To analyze the proteomic profiling of preclamptic placenta compared to that of normal pregnancy for better understanding of pathogenesis in preeclampsia, placentas from each group were handled by use of proteomics approach using 2DE combined with MALDI-TOF-MS. The 20 spots of showing differences were analysed and identified. Among differentially expressed protein spots Hsp 27 and Hsp 70 were selected for validation using Western blot analysis. In preeclamptic placenta 9 differentially expressed proteins were down-regulated with Hsp 70, serum albumin crystal structure chain A, lamin B2, cytokeratin 18, actin cytoplasmic, alpha fibrinogen precursor, septin 2, dihydrolipoamide branched chain transacylase E2 and firbrinogen beta chain. The 11 up-regulated proteins were fibrinogen gamma, cardiac muscle alpha actin proprotein, cytokeratin 8, calumenin, fibrinogen fragment D, F-actin capping protein alpha-1 subunit, Hsp 27, Hsp 40, annexin A4, enoyl-CoA delta isomerase and programmed cell death protein 6. The western blot analysis for validation also showed significant up-regulation of Hsp 27 and down-regulation of Hsp 70 in the placental tissues with preeclmaptic pregnancies. This proteomic profiling of placenta using 2DE in preeclampsia successfully identifies various proteins involved in apoptosis, mitochondrial dysfunction, as well as three Hsps with altered expression, which might play a important role for the understanding of pathogenesis in preeclampsia.