Objective: To observe the efficacy and safety of total glucosides of paeony capsule (TGPC) in patients with mild and moderate alopecia areata. Methods: A total of 86 outpatients were randomly allocated into two groups of TGPC (treatment, 44 cases) and compound glycyrrhizin tablet (control, 42 cases). The treatment group was given oral TGPC, three times daily and 600 mg per time; the control group was given oral compound glycyrrhizin tablets, three times daily and 50 mg per time. In addition, both groups were given 10 mg of vitamin B-2 and tapped the bold patches with massage. The treatment course was three months for both groups. Peripheral blood T-cell subsets (CD3(+)CD4(+), CD3(+)CD8(+), Th, Ts, Th/Ts) of 10 patients randomly selected from each group respectively were tested before and after three months of treatment. The effectiveness and adverse reaction of all cases were observed each month. The safety was evaluated according to the incidence rate of adverse reaction. Results: In the treatment group, the cured and markedly effective rate was 36.36% (16/44), 50.00% (22/44) and 68.18% (30/44) at the end of first, second and third month of treatment, respectively, and the incidence rate of adverse reaction was 13.64% (6/44). In the control group, the cured and markedly effective rate was 38.10% (16/42), 57.14% (24/42) and 71.43% (30/42), respectively, and the incidence rate of adverse reaction was 16.67% (7/42). The cured and markedly effective rate and the incidence rate of adverse reaction were similar in both groups (P>0.05). TGPC and compound glycyrrhizin tablet can inhibit CD3(+)CD4(+) and CD3(+)CD8(+), and decrease the ratio of Th/Ts (P<0.05). Conclusion: TGPC is effective and safe in the treatment of alopecia areata.