Results: 100% success rate of all operation techniques, maximum follow-up time 12 months, 37 cases survived 6 months, half-year survival rate 85.0% (95% CI 0.738-0.962), 30 local lesions PR, 7 NC, clinical efficiency 81.08%, clinical benefit rate 100%. 31 cases survived 12 months, 1-year survival rate 60.5% (95% CI 0.417-0.793), 16 local lesions CR, 7 PR, 2 NC, 6 PD, clinical efficiency 74.19%, clinical benefit rate 80.65%. 0.417-0.793), 16 local lesions CR, 7 PR, 2 NC, 6 PD, 74.19% clinical efficiency, 80.65% clinical benefit rate. 6-month and 12-month KPS scores improved and the difference was significant. Puncture resulted in 3 cases of pneumothorax (6.98%) without serious complications such as injury to large vessels, main trachea, laryngeal recurrent nerve and pericardium. Conclusion: CT-guided radioactive particle implantation for the treatment of intradiastinal malignant tumors or intradiastinal lymph node metastases has a high technical success rate and is relatively safe, with positive efficacy, and should be the preferred treatment technique. The combined application of radioactive particle implantation and endoprosthesis technology will enable more patients to have access to treatment.