Abstract: Objective: to evaluate the clinical effect of rotary files in the root canal treatment（RCT） in aged patients.Methods: 100 aged patients who needed endodontic treatment were randomly divided into two groups. The teeth research included single-root incisors or premolars and multi-root premolars and molars. Test group was processed with rotary Ni-Ti files and control group was with stainless-steel files. The average processing time and post-operate reactions of the two groups were compared statistically.Results: Treatment time of multi-root premolars and molars between the two group was different significantly. Conclusion: Using rotary Ni-Ti files can reduce the time needed for RCT treatment with ideal root canal shape, while facilitate the treatment procedure and ease the patients with high clinical effectiveness.