Behcet’s disease is a multi-systemic inflammatory disease with a clinical spectrum as a triple complex of recurrent oral, genital ulcers, and uveitis. Cardiac involvement in patients with Behcet’s disease is extremely rare and often associated with poor prognosis. Behcet’s disease should be considered in the differential diagnosis of right ventricular mass especially in young adults, even there is no typical clinical features of Behcet’s disease. In this case, a 12-year-old girl who admitted with chest pain and haemoptysis and then was diagnosed with intracardiac thrombus related to Behcet’s disease during follow-up was described.