In the past 20 years, more than 20 cases of a type of granulomatous disease have been noticed by dermatologists in different areas of China. The patients had these features in common: (i) the lesions followed a slight trauma to the face; (ii) they were spreading dark-red plaques without pus or ulceration; (iii) new lesions appeared near to or far from the original lesion; (iv) histopathology showed histiocytic granuloma; (v) the patients had severe headache and clouding of consciousness during the later stages of the disease; (vi) all patients died within 1.5-4 years; (vii) treatment with prednisone led to some healing of the lesions but accelerated death; and (viii) all patients were from rural areas. We examined the tissues from two similar patients by electron microscopy and identified two kinds of bacteria as a possible cause of the disease. One was an anaerobic actinomycete, the other was Staphylococcus capitis. The anaerobic actinomycete was sensitive to lincomycin (a forerunner of clindamycin). After a 5-month therapy with lincomycin, one patient survived. We infer that the cause of death is the unknown anaerobic actinomycete. Because the disease is very severe, we suggest the name 'fatal bacteria granuloma after trauma' to draw attention.