Purpose: The purpose of this study was to describe the premenstrual syndrome and the relationships among premenstrual syndrome, automatic thought, and perfectionism. Methods: The 164 subjects were selected from a nursing college in Tae-Jeon. The data were collected using the PAF, ATQ-N, and MPS from April 10th to May 10th, 2001. Results: The results of this study were as follows : 1. There was no significant difference in premenstrual syndrome due to menarche, duration of menstruation, and menstrual cycle, but significant difference in premenstrual syndrome due to amount of menstruation and regularity of menstrual cycle. 2. The subjects experienced mild premenstrual syndrome. The severe premenstrual syndromes above the mean were who subjects reported general physical discomfort, fatigue, low mood and loss of pleasure, lability and atypical depressive features, et. al., and those below the mean experienced hostility/anger, increased well-being, miscellaneous mood/behavior change, impulsive syndrome and miscellaneous physical changes, et. al. 3. The score of mean premenstrual syndrome was 236.55, that of automatic thought was 31.41 and that of perfectionism was 185.97. The premenstrual syndrome score was similar to those of other studies and subjects had low automatic thought and moderate perfectionism. 4. There were significant correlations among premenstrual syndrome, automatic thought, and perfectionism (P <. 001). 5. Automatic thought and perfectionism accounted for 17 percent of premenstrual syndrome. Conclusions: For future research, it was recommended that the study to identify major factors affecting premenstrual syndrome and the relationships between them with various subjects should be done and effective nursing intervention for premenstrual syndrome should be developed.