Aroma development in rice has been reported due to the lack of function of betaine aldehyde dehydrogenase gene (badh2) on rice chromosome 8. A lot of functional markers have been designed based on the InDels, such as 7bp deletion in exon 2, 803bp deletion in exon 4 and 5, 8bp deletion in exon 7, and 3bp insertion in exon 13. Although there were a lot of functional SNPs, other InDels have not been detected by a PCR-based marker. Here we developed a simple, co-dominant, functional cleaved amplified polymorphic sequence (CAPS) marker for fragrance trait based on 1bp insertion in exon 14. The developed marker showed a high efficiency in discriminating that special aromatic rice variety, and displayed perfect co-segregation with the trait of fragrance in the F2 population. This new marker developed in the present study would be useful in molecular breeding of fragrant rice varieties.