Opsoclonus is a striking disorder of ocular motility. It is generally associated with myoclonus. Although there are many reported cases of opsoclonus in children in association with neuroblastoma, only a few adult cases have been described, Preceding viral infections and underlying malignant tumors are known to be the most frequent causes in adults. We report on four adult cases with opsoclonus. Preceding gastrointestinal and urinary tract infections were present in two of them, while a lung tumor was detected in the third patient. Despite extensive evaluation, the underlying process could not be identified in the fourth patient.