A 35-year-old Chinese female has a large thigh abscess without a clear source. No underlying diseases were revealed in the patient. The combination of clindamycin and cefazolin or vancomycin was administered but without a clinical response. Eikenella corrodens and Streptococcus intermedius were isolated from puncture drainage. Then, ceftriaxone was administered and a surgery of incision and further draining was carried. Eventually, the patient recovered. To our knowledge, this is the first case of thigh abscess in a previous healthy adult.