The purpose of this study was to determine the effect of transcutaneous electrical nerve stimulation(TENS) on the alteration of pressure pain threshold of myofascial trigger points. We used fifty nine patients with upper trapezius mayofascial pain syndrome. Participants classified according to each group in conventional TENS(high rate, low intensity) and acupuncture like TENS(low rate, high intensity). The test was measured continuously pre test, post-test by algometer. The following results were obtained; 1. Pressure pain threshold were significantly increased in all groups(p<.001). 2. In comparison between groups, pressure pain threshold were not significantly differenced. These results lead us to the conclusion that each method by TENS were significantly increased pressure pain threshold of upper trapezius trigger points. Therefore, a further direction of this study will be to provide more evidence that TENS method have an effect on pressure pain threshold of myofascial trigger points.