Adenovirus is an infectious viral agent that causes variety of clinical presentations such as respiratory disease, conjunctivitis, and gastroenteritis. Hepatitis, pancreatitis, myocarditis, encephalitis, and disseminated infection are primarily seen in immunocompromised patients. Rarely, adenovirus infection can present with pertussis-like syndrome. Described here is case of pertussis-like syndrome associated with adenovirus presenting with hyperleukocytosis.