• Morphine acute administration induced downregulation of p-GluN2B (Ser 1303) in the frontal association cortex (FrA) and nucleus accumbens (NAc) of mice. • P-GluN2B (Ser 1303) in the NAc have no influence on morphine-induced conditioned place preference (CPP). • P-GluN2B (Ser 1303) in the FrA involved in the development phase of morphine-induced CPP. • P-GluN2B (Ser 1303) in the FrA have no influence on the extinction phase of morphine-induced CPP. • P-GluN2B (Ser 1303) in the FrA involved in the reinstatement phase of morphine-induced CPP. Morphine is one of the most abused drugs in the world, which has resulted in serious social problems. The frontal association cortex (FrA) has been shown to play a key role in memory formation and drug addiction. N -Methyl- d -aspartate receptors (NMDARs) are abundant in the prefrontal cortex (PFc) and much evidence indicates that GluN2B-containing NMDARs are involved in morphine-induced conditioned place preference (CPP). However, the function of GluN2B in the FrA during morphine-induced CPP has yet to be fully investigated. In the present work, a CPP animal model was employed to measure the expression of phosphorylated (p-) GluN2B (Serine; Ser 1303) in the FrA and NAc in different phases of morphine-induced CPP. We found that p-GluN2B (Ser 1303) was increased in the FrA during the development and reinstatement phases but unchanged in the extinction phase. The use of ifenprodil, a GluN2B-specific antagonist, to block the activity of GluN2B in the two phases attenuated morphine-induced CPP and reinstatement. Furthermore, ifenprodil also blocked morphine-induced upregulation of p-GluN2B (Ser 1303) in the FrA in both phases. These results indicate that GluN2B-containing NMDARs in the FrA may be involved in the regulation of morphine-induced CPP and reinstatement. [ABSTRACT FROM AUTHOR]