Abstract: Fragrance is the most important trait among the domesticated characteristics of rice (O. sativa L.). The recessive fragrance gene on chromosome 8 is associated with rice fragrance. The gene for fragrance in a fragrant rice variety shows the presence of a mutation portion (i.e., an eight base pair deletion in exon 7). This allele is responsible for rice fragrance. In the present study, 65 self-supplied seed lots of black rice (O. sativa L.) from Thailand and Laos were assessed for purity of the fragrance grain of each sample for this locus using a PCR assay. The results indicate that black rice germplasm were genotyped for homozygous fragrant, heterozygote and non-fragrant homozygous. The data from the 65 samples show that 7.7 and 23% of the samples were heterozygous and non-fragrant homozygous, respectively. Heterozygous individuals, black rice plants that carry both the fragrant allele and non-fragrant allele of the fragrance gene and non-fragrant seeds need to avoid because they are non-fragrant and give rise to a mixture of fragrant and non-fragrant seed lots. Therefore, domestication of black rice in order to maintain grain aroma would require the use of quality black rice seed germplasm.