Squamous cell carcinoma in situ (SCCIS) is a histologically confirmed intraepidermal squamous cell carcinoma. The most common cause of Squamous cell carcinoma is chronic ultraviolet light exposure, and other factors include arsenic chemicals, Human Papilloma Virus (HPV), and chronic ulcers. The development of SCCIS on a burn scar is rather rare. Moxibustion is a traditional Oriental medical treatment that involves burning moxa, which contains Artemisia vulgaris, to stimulate certain acupoints. A 93-year-old Korean female presented with a painful, 6 cm by 3 cm, bleeding and crusted ulcer on the abdomen. She has habitually applied moxibustion to relieve abdominal pain on her left abdomen during past several years. Biopsy was performed, revealing full-thickness dysplasia of the epidermis with parakeratosis, acanthosis, loss of polarity, and loss of maturity. The patient was diagnosed with SCCIS awaiting surgical removal. We report an interesting case of SCCIS on the abdomen, which developed on a burn scar secondary to repeated moxibustion.