The high rate of recurrence and chemoresistance necessitates in ovarian cancer warrants further research into tumor markers characterizing the resistant population. The proportion of drug-resistant tissue cells in residual lesions after neoadjuvant chemotherapy increases, and drug-resistant markers are enriched. However, there is a lack of comprehensive understanding of tumor marker predoninance pre- and post- neoadjuvant chemotherapy. Here we performed quantitative proteomic analysis of TMT in three patients with matched pretreatment biopsies and post-NACT ovarian cancer tissues. This study highlights a dominant molecular subpopulation that persists in the ovary after neoadjuvant chemotherapy exposure in order to elucidate how it is involved in mediating chemotherapy response, which will lay the foundation for the development.