Mammalian oocytes are arrested at meiosis prophase I due to high intracellular concentration of cyclic adenosine monophosphate (cAMP) that keeps protein kinase A (PKA) active, which phosphorylates and inactivates M-phase inducer phosphatase 2 (CDC25B) and mitosis promoting factor (MPF). The pre-ovulatory surge of luteinizing hormone releases the meiotic arrest by declining intracellular [cAMP] – this results in maturation of the oocyte into a fertilizable egg. 14-3-3 proteins regulate various intracellular events including cell cycle control, and are thought to bind to and sequester phosphorylated CDC25B in the cytoplasm of oocytes, arresting oocytes at meiosis prophase I. We previously identified CDC25B and all seven mammalian isoforms of 14-3-3 in mouse oocytes and eggs. The present study, using Duolink II in situ Proximity Ligation Assays (PLA), reveals prominent interaction of all isoforms of 14-3-3 with CDC25B throughout cytoplasmic as well as nuclear compartments in mouse oocytes and eggs. However, marked reduction in the numbers of Duolink II fluorescent reaction spots are noted in eggs as compared to oocytes, consistently in multiple experiments, for interaction of CDC25B with all 14-3-3 isoforms, except 14-3-3 tau. These results and further studies will elucidate the importance of 14-3-3 protein interactions with CDC25B in mammalian oocyte maturation.