Miller Fisher syndrome (MFS) is an immune mediated neuropathy commonly triggered by an infection. It is considered as a variant of Guillain-Barre syndrome. Although bilateral ophthalmoplegia is the commonest ocular involvement in MFS, there are reported cases of unilateral ophthalmoplegia. MFS has a benign course and treatment is not required in majority of cases unless there is a lifethreatening complication.We report an unusual case of MFS, presented with isolated right sided oculomotor nerve palsy with pupillary involvement, ataxia and areflexia. Patient was treated with intravenous immunoglobulin (IVIG) achieving a remarkable recovery by five days of treatment. We believe this is a treatment effect rather than the natural course of her illness. Although it is rare, MFS should be included in the differential diagnosis of unilateral 3 rd nerve palsy with pupillary involvement, especially when associated with ataxia or areflexia. Having a low threshold to initiate IVIG in MFS may accelerate the recovery with a positive impact on patient's functional status.