Purpose To report a case of lacrimal gland adenoid cystic carcinoma (ACC) with an atypical initial presentation and to postulate an anatomical explanation for this unusual biologic behavior. Design Interventional case report. Methods An orbital magnetic resonance imaging study of a 58-year-old man who complained of progressive diplopia and orbital discomfort disclosed a soft tissue mass in the left cavernous sinus and orbital apex. The left lacrimal gland and the contiguous bone appeared normal. Results Biopsy of the intracranial mass revealed ACC of unknown origin which was judged to be unresectable. He underwent two cycles of intraarterial cytoreductive chemotherapy followed by a left medial maxillectomy with sphenoethmoidectomy, orbital exenteration, and chemoradiation. ACC tumor cells were identified in nerve fiber bundles surrounding and within the lacrimal gland. Conclusions In patients presenting with an infiltrative mass in the cavernous sinus or orbital apex, metastatic disease from an occult lacrimal gland primary should be considered, even with a normal-appearing lacrimal gland.