The purpose of this quasi-experimental study was to explore the differences in the effect of aromatherapy according to the type of Sasang constitution. The subjects were fifty-three nursing students experiencing clinical practice from March 10th. 2000 to April 22nd, 2000. For experiment, researcher used inhalation of 2% grape seed oil mixed with Rosemary oil for 2 minutes and massage with same oil for 20 minutes on the back of subjects in the speed of 20 strokes per minutes. The instruments used for this study were Questionnaire of Sasang Constitution Class II program for personal computer developed by Kim Sun Ho et al., (1996), and Mood Questionnaire developed by Ryman. Biersner, & Larocco (1974). The concentration of IgA within saliva was analyzed by immunoturbidimeter assay. The data were analyzed using SPSS and hypotheses were examined with paired t-test and ANCOVA. The results were as follows : 1) The mean score of mood was increased significantly after aromatherapy. 2) The mean concentration of salivary IgA was increased significantly after aroma therapy. 3) There was no significant difference in the mean score of mood after aromatherapy according to the type of Sasang constitution, 4) There was no significant difference in the mean concentration of salivary IgA after aromatherapy according to the type of Sasang constitution. In conclusion, the results suggest that aromatherapy with Rosemary oil have effect on the improvement of mood and IgA within saliva in the nursing students under stress caused by clinical practice regardless of the type of Sasang constitution.