One hundred twenty patients with acute and chronic pain treated by a low power laser were divided into several groups by their pathology and evaluated according to their response rate to laser therapy through a follow-up study. 1) The ages of the patients were between the early twenties and late forties (71.7%), and there was no differences between sexes. 2) The spinal pathology group was the most common(52.5%) and the articular pathology group occupied next (14.2%). 3) The average duration of Laser therapy was about 20 days and response to the therapy appeared about the eighth day. 4) The response to the therapy in the spinal pathology group appeared about the eighth day and the average duration of therapy was about 18 days. 5) The response to the therapy in the articular pathology group appeared about the eighth day and the average duration of therapy was about 28 days. 6) The response rate of the spinal pathology group was 81.0%, and remarkable symptom relief was noted when compaired to a 58.7% response rate in the control group, 7) The response rate of the articular pathology group was 82.4%, which was similar to the control group. 8) The response rate of the miscellaneous group was 87.0%, and remarkable symptom relief was noted when compaired to a 66.7A response rate in the control group. 9) The mean response rate of all patients treated by a low power laser was 82.5% and that of the control group was 70.5%. Laser therary proved to be an effective treatment modality for acute and chronic pain.