Traumatic ulcerative granuloma with stromal eosinophilia (TUGSE) is a benign lesion of the oral mucosa of an unclear pathogenesis. We analyzed the profile of the inflammatory infiltrate in 12 cases of TUGSE by using immunohistochemical analysis and polymerase chain reaction-based repertoire analysis to detect T- and B-cell receptor gene rearrangements. The inflammatory infiltrate consisted in most cases of B and T lymphocytes, macrophages, abundant eosinophils, and large atypical cells. In 5 cases, CD30+ cells were found. Spectratyping analysis displayed a polyclonal rearrangement of the T-cell receptor g gene in 6 cases and oligoclonality in 5 cases. Monoclonality was observed in 1 case that also fulfilled histologic criteria for lymphoma. Healing was uneventful in all cases, including the one suspected of being lymphoma, with no recurrences in more than 2 years'follow-up. TUGSE can be regarded reactive. Some cases, however, may harbor a dominant clonal T-cell population; in these cases, long-term follow-up is mandatory.