Enhancing the pulmonary annulus renders the pulmonary valve incompetent in cases of tetralogy of Fallot. A pressure-loaded right ventricle may change to a volume-loaded ventricle, which may dilate and eventually dysfunction. This study evaluated a new technique of fashioning a monocusp valve from untreated autologous pericardium suspended on a transannular patch. It was assessed in 40 children undergoing complete repair of tetralogy of Fallot between January 2005 and December 2007. 24 patients had a transannular patch alone (group A) and 16 received a transannular patch with the autologous pericardial monocusp valve (group B). All patients were followed up for 1 year with transthoracic echocardiography to determine pulmonary insufficiency. There was no significant difference in cardiopulmonary bypass or aortic crossclamp times, postoperative chest tube drainage, duration of inotropic usage, intensive care unit or hospital stay between groups. Univariate analysis showed significantly lower grades of pulmonary insufficiency in group B. This technique for creating an autologous pericardial monocusp valve is an inexpensive, simple, and reliable procedure that effectively reduces pulmonary insufficiency at the 1-year follow-up.