Maturation/M-phase promoting factor (MPF) activity is regulated by the Cyclin B concentration and phosphorylation states of Cdc2 kinase. In the present review, we summarize the factors regulating the synthesis and degradation of Cyclin B and the phosphorylation and dephosphorylation of Cdc2. We focuse on Aurora A and cytoplasmic polyadenylation element binding protein (CPEB), which are involved in cytoplasmic polyadenylation, for Cyclin B synthesis; on anaphase-promoting complex (APC) activating factors, FZR1 and CDC20, for Cyclin B degradation; on Cdk7 and Wee1B for Cdc2 phosphorylation, and on Cdc25 for Cdc2 dephosphorylation. We describe our recent results concerning these factors in porcine oocytes, and discusse overall regulation of MPF activity during porcine oocyte maturation.