A bidirectional mapping catheter is provided. The catheter comprises an elongated flexible tubular catheter body having an axis and proximal and distal ends. A mapping assembly, which is mounted at the distal end of the tubular body, has a preformed generally circular main region having an outer surface that is generally transverse to the axis of the catheter body. The generally circular main region has proximal and distal ends and carries a plurality of spaced apart electrodes. An electrode lead wire is associated with each electrode. Each electrode lead wire has proximal and distal ends and extends through the catheter body and into the mapping assembly. The distal end of each electrode lead wire is electrically connected to its associated electrode. First and second puller wires are provided. Each puller wire has proximal and distal ends and extends through the tubular catheter body. The distal end of each puller wire is anchored at or near the distal end of the catheter body. A handle is connected to the proximal ends of the catheter body and puller wires for moving the puller wires longitudinally relative to the catheter body. Longitudinal movement of a puller wire relative to the catheter body results in deflection of the distal end of the catheter body.