Objective This paper is to study clinical efficacy of mere radiotherapy applied to treat patients with nasopharyngeal carcinoma at sub-stage T and sub-stage N. Methods One hundred and thirty two patients with nasopharyngeal carcinoma (NPC) were selected as research subjects, all of those patients completed the treatment and followup as of October, 2014, and the manner of control study was applied to divide them into two groups with 60 patients at T sub-stage group and 72 patients in N sub-stage group, patients in two groups were subject mere radiotherapy treatment, clinical efficacy and adverse effects of patients in two groups were summarized. Results There was no significant difference in the rate of complications of patients in two groups, the total effective rate of patients in T sub-stage group and N sub-stage group hit 80% and 84.7% respectively, the comparison in the recurrence rate, metastasis rate, rate of recurrence and metastasis, three-year survival rate and five-year survival rate hit χ2 =7.31, 10.43, 7.74, 10.43 and 7.74 respectively with average P<0.05, and the difference was statistically significant. Conclusion Mere radiotherapy applied on patients with nasopharyngeal carcinoma delivers efficacy, the prognosis and outcome of illness are associated with N sub-stage and T sub-stage, while the N sub-stage serves as the leading factor, and stratified radiotherapy can facilitate improving clinical efficacy of patients.