The ultrasonic metal welding method generally uses unidirectional vibration locus. However, this method has different weld strength depending on the direction of welding target installation. To solve this problem, we investigate ultrasonic metal welding by complex longitudinal-torsional vibration which is non-directional vibration. We study focusing on the planar vibration locus among the complex longitudinal-torsional vibration. We developed a dumbbell-shape vibration source with longitudinal and torsional transducers with excellent vibration controllability.