The purposes of this study was to describe premenstrual syndrome, dysmenorrhea, and relieving practices of female students in Prince of Songkla University. The sample comprised 246 female undergraduate students selected by stratified random sampling. The data collection instrument was a premenstrual syndrome and relieving practices questionnaire. Data were analyzed using percentage, arithmatic mean, standard deviation, and dependent t-test. The results showed that all female students had at least one mild, moderate or severe premenstrual symptom. The incidence of premenstrual syndrome slightly increased from the seventh day before menstrual flow to the first day after menstrual flow, and the incidence of premenstrual syndrome slightly decreased until the seventh day. On the first day before menstrual flow, the most common symptoms were breast tenderness ( 68.7% ), irritability ( 58.9% ), abdominal pain ( 56.9% ), acne ( 56.5% ), and low back pain ( 53.3% ). During the first day of menstrual flow, the most common symptoms were abdominal pain ( 77.6% ), irritability ( 63.8% ), breast tenderness ( 63.0% ), low back pain ( 61.4% ), fatigue ( 60.6% ), and acne ( 58.1% ). The most severe premenstrual syndrome affecting daily activities was abdominal pain ( 5.7% ). Almost half ( 41.5% ) used some medications to relieve the abdominal pain. The other relieving practices were hot compresses, drinking warm water, self-massage, aerobic exercise, yoga, and rest or sleep. Premenstrual syndrome significantly decreased after using medications or other relieving practice (  p   <   0.05 ).