Pericardial effusion complicated by cardiac tamponade is a medical emergency. Large pericardial effusion and tamponade are rare in childhood. Tuberculosis remains a major cause of pericardial effusion in endemic areas. A 16-year-old adolescent with no significant past history was admitted to the medical unit of the Buea Regional hospital in the South West region of Cameroon for heart failure after presenting with abdominal distension, shortness of breath and fever of two weeks duration. Echocardiographic study during admission revealed a large pericardial effusion (27mm in thickness) with echocardiographic signs of tamponade. Echocardiographic guided pericardiocentesis was performed through a sub-xiphoid route and about 500 cc of heavily stained blood fluid that was not coagulating was drained. Pericardial fluid analysis for acid fast bacilli was negative. There was no evidence of malignancy. A strong suspicion of tuberculosis was made and he was started on anti-tuberculosis medications for presumptive hemorrhagic tuberculous pericarditis. Patient was asymptomatic during follow up and repeat echocardiographic examinations showed no re-accumulation of pericardial fluid. Tuberculosis should be considered as the etiology of pericardial effusion in endemic areas although the identification of mycobacterium is challenging in these settings.