The common prion protein gene (PRNP) codon 129 polymorphism is a strong susceptibility factor for human prion diseases. In this study, we examined the allelic variation of methionine and valine at codon 129 in 147 subjects representing the normal Moroccan population. The sharing of the genotype was 57.1% for Methionine-Methionine (MM), 36% for Methionine-Valine (MV), and 6, 8% for Valine-Valine (VV). These results are indeed intermediate between those discovered at the European and Asian populations. However, and for a better assessment of the risk to develop prion diseases in the Moroccan population, the survey of the frequency of the codon 219 polymorphism is required.