Cell-to-cell and cell-to-matrix communication is fundamental for ovarian follicle development and oocyte maturation. Among the mediators of this communication are large-pore channels formed by Connexins (Conx) and Pannexins (Panx). Panx1, a key member of the Panx family, has been implicated in impaired follicle growth and reduced oocyte viability. Here, we examined the localization of Panx1 within mouse ovarian follicles and evaluated its expression during in vitro oocyte maturation. Panx1 distribution and levels in germinal vesicle (GV), metaphase I (MI), and metaphase II (MII) oocytes were analyzed using immunofluorescence, Western blot, and qRT-PCR. Panx1 expression intensity did not differ significantly among follicular stages in either follicular oocytes (p = 0.179) or follicular cells (p = 0.150). However, signal intensity was higher in cumulus-free GV oocytes compared with cumulus-enclosed GV oocytes and significantly decreased (p < 0.05) from GV to MII. Western blot results showed stable protein levels across GV, MI, and MII stages, whereas Panx1 mRNA showed a trend toward increased expression as maturation progressed. Overall, these findings demonstrate Panx1 localization and expression during follicular development and oocyte maturation, providing a descriptive basis for future functional studies.