The floral scents of three forms of cultivated Plumeria rubra L. were evaluated through mass flowering phenology using the dynamic headspace adsorption method and were identified with coupled gas chromatography and mass spectrometry. The forms P. rubra f. acutifolia and P. rubra f. lutea had white and yellow flower petals, respectively, and the flower petals of P. rubra f. rubra were red. Although 68 components of the flower scents of the three forms were recorded in different proportions, only 14 chemical compounds were identified with statistically significance. The main volatile compounds in the red form of P. rubra L. were fatty acid derivatives (56.75%). The main compounds in the white and yellow forms of P. rubra L. were benzenoid and terpene, with proportions of 48.38% and 33.33% in P. rubra f. acutifolia and proportions of 42.30% and 47.43% in P. rubra f. lutea, respectively. These differences in the flower scents might be one result of the minor genetic differences between these forms, similar to the role of genetic differences in the flower color combinations of the three forms. We conclude that petal color traits can, to some extent, reflect differences in floral scent compositions and that minor genetic differences of different plant forms exert impacts not only on flower color but also on the phytochemistry of floral scents.