Wheezing is one of the most common symptoms in childhood and it can be caused by a variety of conditions. Viral infections, which are one of the most common causes of wheezing, generally lead to conditions of bronchiolitis and wheezing that respond well to supportive and short-acting bronchodilator treatment. A diagnostic algorithm extending even to bronchoscopy should be applied to children with persistent wheezing. Cytomegalovirus (CMV) is commonly seen in healthy people and generally leads to asymptomatic infections. However, CMV can sometimes lead to symptomatic infections in healthy people as well. In this article, a case of CMV pneumonia diagnosed in an infant with persistent wheezing who responded well to ganciclovir treatment is presented.