This study was to determine whether iontophoresis application would produce analgesic effect for clinical practice. Physical therapist controls pain produced by various causes and plays a role improving functional disability. I studied varieties of pain theories, mechanisms and iontoporosis principles which need for physical therapist. These were summarized as follwings; 1 . In the case of chronic patients, it is helpful to adapt iontophoresis treatment as well as generalized treatments which goals for pain releasc. 2. lontophoresis treatment should be positively examined to control pains safely. efficienently without sideeffects. 3. lontoporesis treatment suggests the foundations that hormone or anaesthetics should be incluided in the range of medicines physical therapist can deal with.