WEE2, also named as WEE1B, belongs to the protein kinase superfamily. Ser/Thr protein kinase family and WEE1 subfamily. It phosphorylates and inhibits CDK1. WEE2 may act as a negative regulator of entry into mitosis (G2 to M transition). WEE2 is conserved from yeast to humans. The aim of the present study was to determine the spatiotemporal expression pattern and the function of WEE2 during oocyte maturation in a nonhuman primate species, the rhesus macaque. Taking the long double-stranded RNA-mediated RNA interference approach, down-regulation of WEE2 led to meiotic resumption in a subset of GV oocytes even in the presence of a phosphodiesterase 3 inhibitor. Overexpression of WEE2 delays the reentry of oocytes into meiosis in both mice and monkeys. WEE2 is a conserved oocyte-specific meiosis inhibitor that functions downstream of cAMP in nonhuman primates.