A patient with drug refractory supraventricular tachycardia showed electrophysiological evidence of bilateral quadruple accessory pathways. The conduction was bidirectional in the left posteroseptal and left posterolateral accessory pathways, antegrade in the right lateral accessory pathway, and retrograde in the right anterior accessory pathway. The four pathways participated in seven types of reciprocating tachycardias. Radiofrequency ablation eliminated the four pathways successfully. The patient was asymptomatic and free of any drug during a 10-month follow-up.