Kasabach-merritt syndrome is a rare life-threatening syndrome associated with vascular tumors such as tufted angioma and kaposiform hemangioendothelioma. For this syndrome, there exist a few treatment modalities with variable results. For many years, corticosteroids have been employed in the first-line therapy. Nowadays, on the other hand, β blockers such as propranolol have been used owing to their acceptable efficacy and fewer side effects. In the present case report, atenolol combined with corticosteroid was, for the first time, prescribed for the treatment of the syndrome; a significant improvement was observed with no concomitant side effects.