Purpose: To evaluate a case of orbital actinomycosis presenting as Tolosa-Hunt syndrome in a patient with a history of carcinomas of the kidney and breast. Methods: A woman with ingravescent painful ophthalmoplegia was brought to our observation. Brain and orbital and total body CT scans showed the presence of two orbital neoformations and a miliary pattern of dissemination in the lung. The initial diagnosis, which pointed to secondary localisations of the previous kidney and breast tumours, was changed to orbital and pulmonary actinomycosis following microbiological analysis of lung biopsy samples. Results: Prolonged antibiotic therapy with synthetic penicillin completely resolved the case. Conclusions: Actinomycosis is a very rare infection that may also affect the orbit and its association with a pulmonary dissemination is highly unusual. It is important to consider this type of infection among the causes of painful ophthalmoplegia.