Objective: This study aimed to report the improvements of with nummular eczema treated using Osuyu-tang based on Shanghanlun provisions.

Methods: According to the disease pattern identification diagnostic system based on the the patient was diagnosed with lesser-yin disease. The patient was treated with Osuyu-tang for 60 days. The severity of the patients’ pruritus decreased, and changes in symptoms were assessed using visual analogue scale score and vIGA-ADTM

Results: The patients' symptoms improved, pruritus decreased, and abrasion healed.

Conclusions: The results suggest that the words on the 309th provision of Shanghanlun are a direct cause of nummular eczema.

Keywords: Osuyu-tang, Nummular eczema, Shanghanlun