For aromatherapy research, it is necessary to determine how the autonomous nerve system activities are influenced by fragrance. In this paper, the effect of jasmine fragrance on the autonomous nerve system was examined for a subject in terms of changes in HF (high frequency) and LF (low frequency) components of the power spectra of pulse rate fluctuations. The LF component increased significantly (p<0.01), although the HF component had no significant change for the subject. The experimental result suggested that the activity of the parasympathetic nerve was increased by jasmine fragrance.