The present invention relates an electrochemical processing apparatus and a processing method thereof. A reciprocating swing unit is used to drive the processing electrode to process a workpiece, and thus simplifying fabrication of the processing electrode, and shortening processes and reducing costs. In addition, by using a high-frequency reciprocating twist and micro-vibrating unit to drive the processing electrode to perform high-frequency reciprocating twists and micro-vibrations, the processing electrode can perform twist without varying the processing gap. Thereby, the electrolyte in the gap can be perturbed and renewed continuously. Accordingly, bubbles and products produced during electrolysis can be removed sufficiently, enhancing processing precision and surface quality using the processing electrode on processing the workpiece.