Abstract: Objective To analyze, research and process curative effect and damaging effect of terminal non small cell lung carcinoma(NSCLC). Methods Under treatment planning system and CT image guided, ¹²⁵I seeds were implanted in 89 case confirmed terminal NSCLC and posologic validation and recheck termly. Results The total efficient rate of brachytherapy and chemotherapy group respectively is 97% and 20%. They have the significant difference(χ²=64.92, P<0.01). Conclusion The therapy of radioactive ¹²⁵I seeds implantation is resulfful. But it unavoidably has low-grade damaging effect.