Objective To introduces the surgical technique and preliminary clinical results of Ulnar shortening osteotomy combined with reconstruct the ligaments for the treatment of chronic distal radioulnar joint instability Methods 16 patients with chronic distal radioulnar joint instability were treated in our hospital with Ulnar shortening osteotomy combined with reconstruct the ligaments．Longitudinal incision was made on the dorsal ulnar side of the forearm to expose the ulnar diaphysis, The ulnar shortening osteotomy was performed according to the measurement of the ulnar variation length before operation, and the osteotomy end was fixed with locking plate.The palmaris longus tendon was cut and the distal radioulnar joint ligament was reconstructed according to Adams&Berger method. Results All patients were fully followed up. Postoperative follow-up time was 12-18 months, with an average of 15.06 months.postoperative motion of the wrist joint was improved to a certain extent.At the last follow-up, the mean score of modified Mayo wrist function in 16 patients was 89.81 points, including 9 excellent cases, 5 good cases, 2 ok cases and 0 poor cases. The good rate is 87.50%. Conclusion Ulnar shortening osteotomy combined with reconstruct the ligaments for the treatment of chronic distal radioulnar joint instability can achieve satisfactory clinical efficacy in the short term, Wrist function was significantly improved.It's a good treatment.