The effect of the magnetic necklace on chronic neck and shoulder pain was studied on 101 volunteers, 46 males and 55 females. A double-blind method was applied on 4 divided groups (with pain vs without pain matched with magnetic vs nonmagnetic necklace). All the subjects wore the necklace 24 hours per day for 3 weeks. Subjective evaluation from the subjects with pain, either with magnetic or nonmagnetic treatment, was performed before and 3 weeks after the necklace treatment, and revealed a significant placebo effect in terms of decrease in intensity or frequency of pain. The objective tests with electrodiagnostic procedures were done before the treatment and at 3 weekly intervals. The proximal conduction time of the ulnar nerve was significantly reduced by magnetic treatment in the subjects without pain but was not changed in the subjects with pain. There was no significant change in the excitation threshold of the suprascapular nerve in all subjects. The possible mechanism of magnetic effects on pain and the prospect of magnetotherapy for pain relief in physical medicine are discussed.