During a 3 year period from 1978 to 1980, one hundred and seventeen patients who came to the Pain Clinic of the Department of Anesthesiology of the Osaka Medical College complaining of pain, were treated with leaving needle(LN), direct current electrical acupuncture (EAP), or low-frequency electrical acupuncture(LFEA). The immediate effects of these therapies were investigated in a period of 3 days after treatment, on the basis of the patient's subjective evaluation of his relief from pain on a scale of 10 before treatment. Appearance patterns of therapeutic effects of these therapies were divided into four types: persistent (therapeutic effects persist during the 3 day period immediately after treatment), downward (therapeutic effects gradually decrease immediately after treatment), upward (therapeutic effects gradually appear after treatment), and unaltered (therapeutic effects were fair or poor during the 3 days after treatment). In addition, it was seen that of the three therapies LFEA was the best one in producing a persistent therapeutic effect and a good rate of effectiveness in the first day immediately after treatment.