The introgressed parental genomes of Elaeis oleifera x Elaeis guineensis(OxG) hybrids were investigated using the genomic in situ hybridization technique. This technique was able to show clear differentiation between the E. oleifera and E. guineensis genome. It was observed that there are 16E. oleifera and 16 E. guineensis chromosomes in the OxG hybrids. The interphase nuclei of the OxG hybrids had groups of chromosomes from both parental genomes in discrete, non-intermixed domains.