An 84-year-old woman developed a markedly proptotic right eye with external ophthalmoplegia and displacement of the globe into the superotemporal orbit. She had minimal pain and no history of the usual predisposing causes of orbital cellulitis. Vision was unaffected. Orbital computed tomography (CT) showed an extraconal inferomedial abscess with an adjacent intraconal component. A purulent abscess in the anterior inferomedial aspect of the orbit, which extended into the medial aspect of the intraconal space, was incised and drained. After surgery, the orbital inflammation and proptosis resolved, but an irreducible, nonpurulent lacrimal sac mucocele persisted. A dacryocystectomy was performed. Pathologic examination of the lacrimal sac biopsy specimen showed only chronic nongranulomatous inflammation. This case demonstrates that acute dacryocystitis may cause an intraconal orbital abscess with proptosis and complete external ophthalmoplegia, and represent a sight- and life-threatening condition.