Arachnoid cysts are relatively uncommon in infancy and are incidental findings in intracranial imaging in pediatric patients. Presentation at a younger age is usually associated with cyst enlargement. Arachnoid cysts are considered to be congenital in origin but the natural history and prevalence is not well defined. Here we report a case of a 2 months old male infant with non-specific illness who was diagnosed with arachnoid cyst.