The diagnosis of ocular myasthenia gravis is rarely in doubt in patients with a proper history and typical clinical findings. However, myasthenia gravis can mimick any pupil-sparing eye movement disorder and several diseases may masquerade myasthenia gravis. We review the atypical presentations and differential diagnoses in ocular myasthenia gravis, describing four patients with some of these conditions (4th nerve palsy, near spasm reflex, one-and-a-half syndrome, orbital meningioma). The correct interpretation of the clinical findings associated with appropriate neuro-imaging studies allowed the appropriate diagnosis in these cases.