The authors report the successful treatment of a 42-year-old man who suffered from recurrent painful ophthalmoplegia caused by bilateral cavernous sinus (CS) actinomycosis. A presumptive diagnosis of Tolosa-Hunt syndrome was made when he presented with left painful ophthalmoplegia. Recurrent ophthalmoplegia on the opposite side when steroid medications were tapered led to repeated imaging and a pterional craniotomy and biopsy sampling of the CS. These tests demonstrated acute inflammation and sulfur granules, which responded clinically and radiologically to parenterally administered penicillin therapy. Actinomycosis may present as a painful ophthalmoplegia with involvement of one or both CSs. Repeated imaging and possibly surgical exploration may be necessary to make a definitive diagnosis.