A cancer electrochemical-therapeutic device using electrothermal needles, comprising two groups of electrothermal needles and three D.C. power supplies, each group having at least one electrothermal needle, two of the three D.C. power supplies - serving as heating power supply - being connected to the groups of electrothermal needles to heating them to realize electrothermal therapy, and the other D.C. power supply - serving as electrochemical power supply - being connected to the corresponding electrodes of the D.C. power supplies to realize electrochemical therapy between twoelectrothermal needles. The device is simple, easy to use and reliable, its cost is low and its therapy effect is good.