Background Although there is a standard guideline for the treatment of acne, it is still a common skin disease, and suboptimal medication adherence is a major reason for treatment failure. Herbal extracts are an interesting alternative medicine because they consist of a variety of active ingredients. Moreover, herbal extracts may have improved therapeutic efficacy because of the combination of various herbs. Objectives To evaluate the effectiveness of herbal extracts for the treatment of mild to moderate acne vulgaris. Methods A total of 77 patients were randomized to receive either an herbal extract or 2.5% benzoyl peroxide, which were applied for a period of 12 weeks. Acne lesion counts, adherence, porphyrin counts, the Dermatology Life Quality Index, satisfaction and side effects were assessed. Result At the 12‐week point, the acne lesion counts decreased, with statistically significant differences from the baseline values in both groups and for all types of acne (P‐value < 0.001). The adherence rate was significantly higher in the patients using the herbal extract than in the patients using 2.5% benzoyl peroxide (P‐value = 0.002). There was no statistically significant difference in terms of porphyrin counts, spot scores, the Dermatology Life Quality Index or satisfaction with efficacy between the groups; however, satisfaction with drug administration was significantly higher in the patients using the herbal extract (P‐value = 0.001). Conclusion Herbal extracts could be beneficial for anti‐acne pharmaceutical preparations and may be used as an alternative medicine for patients with mild to moderate acne vulgaris who do not adhere to benzoyl peroxide treatment.