This paper is a case report of gangrenous pyoderma (PG). Under the guidance of Traditional Chinese Medicine (TCM) theories, the six-meridian differentiation syndrome was primarily applied with the consideration of eight principles, qi and blood, and zang-fu viscera differentiation. Patients in the study received mainly herbal medicine, as well as antibiotics, surgical debridement and nutrition support, etc. This case report provided clinical experience on TCM treatment principles and methods of PG in combination with modern medicine. It further provides ideas for syndrome differentiation and treatment of diseases such as ulcer and carbuncle in TCM.