This paper studies the efficiency differences between multi-axis and single-axis EDM using a spark link algorithm. A main direction ingestion interpolation algorithm was designed and developed, based on various linkage requirements and EDM process characteristics. Compared with the traditional point-by-point comparison method, this algorithm can improve linkage efficiency. By analyzing the consumed acceleration and deceleration time and continuous motion time, the efficiency of single-axis and linkage interpolation under non-discharge and discharge conditions was compared. The results show that multi-axis linkage has a significant efficiency loss compared to single-axis motion. Furthermore, the main direction ingestion interpolation algorithm can effectively reduce the efficiency loss caused by linkage. Under non-discharge conditions, the maximum value of efficiency loss for two-axis linkage is about 25.47%, and the maximum value of efficiency loss for three-axis linkage is about 46.30%, and the results fluctuate depending on the continuous feed ratio of single-axis motion. Under discharge conditions, in terms of material removal rate comparisons, the two-axis linkage improved by about 7.91%, and the three-axis linkage improved by about 11.92%.