Two platinum electrodes were inserted into malignant cancer tissue. One electrode was positive or anode, and the other was negative or cathode. Five to thirty milliamperes were employed between two electrodes. The tissue impedance was initially 600 ohms and decreased to 300 ohms in 30 minutes following the start. Marked acidosis was obtained around the anode, while strong alkalosis was created around the cathode. Cancer tissues of 2cm in diameter around the electrode became necrotic in 60 min. This principle was applied for the local destruction of cancer tissues. Repeated use of direct current seemed to be effective in decreasing the cancer volume around electrodes. For more complete destruction of the cancer tissues, bleomycin was injected intravenously in experimental animals. Since the agent was positively charged, it was easily drawn toward the negative electrode. Direct current was applied following the bleomycin injection, and animal tissues around electrodes were examined. The drug was found to accumulate around the cathode in 6 out of eleven cases. The use of direct current might be helpful in accumulating anti-cancer drugs in malignant tissue.