The allelic diversity within oil palm populations (45 native ones from 10 African countries, three breeding populations and one collection of semi-wild material) was determined using 16 microsatellite markers. A total of 209 alleles were detected, with a mean number of 13.1 alleles per locus. The mean effective number of alleles per locus (Ae) was 3.3 ^ 1.3. Although the Duncan's multiple range test only separated the group of populations from Madagascar from the rest on the basis of Ae, the presence of unique and rare alleles and high values of Ae suggest that 23 of the African populations should be conserved to secure allelic diversity.