Abstract：Objective：To observe the clinical effect of “origin-insertion area theory” in the treatment of lateral epicondylitis of humerus by acupotomy. Methods： A total of 60 cases of patients with lateral epicondylitis of humerus were divided into the observation group and the control group according to the random number table method， with 30 cases in each group. The observation group was treated with acupotomy，and the control group was treated with block therapy. Visual Analogue Scale (VAS) scores and Mayo Elbow- Performance (Mayo scores) before and after treatment as well as the clinical effects were compared between the two groups. Results：Before treatment，there was no significant difference being found in the comparison of VAS scores of elbow pain between the two groups (P＞0.05). After treatment， VAS scores in the two groups were decreased (P＜0.05)，and the score in the observation group was lower than that in the control group (P＜0.05). Before treatment，there was no significant difference being found in the comparison of Mayo scores between the two groups (P＞0.05). After treatment，Mayo scores in the two groups were increased (P＜0.05)，and the score in the observation group was higher than that in the control group (P＜0.05). During the two-week follow-up after treatment，the total effective rate was 100% in the observation group and 93.33% in the control group， there being no significant difference between the two groups (P＞0.05). During the three-month follow-up after treatment，the total effective rate was 96.67% in the observation group，higher than that of 76.67% in the control group (P＜0.05). Conclusion： The clinical application of “origin-insertion area theory” in the treatment of lateral epicondylitis of humerus by acupotomy has a quite good effect，which can effectively reduce pain and improve elbow joint function， with a good long-term curative effect.