Echocardiographic features were studied in four patients with straddling tricuspid valve, a rare and complex cardiac anomaly that may defy diagnosis by angiocardiography. The most significant echocardiographic feature was a septal echo recorded at a depth corresponding to the midportion of the tricuspid valve with one of the tricuspid valve leaflets opening posterior to the ventricular septum in diastole. Certain of the features, which appear to be distinctive for this anomaly, have not previously been described.