In Taiwan, approximately 46% of women during perimenopause have experienced perimenopausal syndrome, which mostly includes insomnia, hot flushes and sweating, and palpitation. Hormonal replacement therapy (HRT) is the mainstream treatment of perimenopausal syndrome. However, many women suffering from perimenopausal syndrome would prefer to take Guilu Erxian Jiao (GEJ) rather than receive HRT. Therefore, the aim of this study is to determine whether GEJ helps relieve perimenopausal syndrome. We treated perimenopausal women who suffered from perimenopausal symptoms and divided them into three groups, administering GEJ at 200 mg per day, 100 mg per day, and a placebo (GEJ-free starch powder), all of which were in the same capsule form with one capsule administered per day for 2 months. Serum estradiol and follicle-stimulating hormone (FSH) levels were tested at three stages: pre-treatment, 1-month post-treatment, and 2-month post-treatment. The clinical symptoms were estimated using the questionnaire of physical and mental symptoms during perimenopause before and after 2 months of treatment. After 2 months of treatment, serum estradiol levels were significantly elevated in the high-dose group (200 mg/day) (P＜0.05). However, no significant differences of serum FSH levels were observed among the three groups after GEJ treatment. Although improvements were observed in both the high-dose and low-dose groups, more amelioration in clinical symptoms was noted in the low-dose group (100 mg/day) than in the high-dose group, especially for hectic sweats and palpitation. GEJ is effective for relieving perimenopausal syndrome, and taking high-dose GEJ once per day for 2 months elevates more serum estradiol levels than does taking a low dose. Therefore, we concluded that GEJ is beneficial for treating perimenopausal syndrome.