Abstract: Objective : To investigate the resolving time of the residual neck metastases in NPC patients after radiotherapy, to analyse possible factors in effect. Methods : 80 analytically sampled cases, from May 1998 to June 2003, of the residual neck metastases in NP c patients after radiotherapy were collected and studied. An investigation of the resolving time of these residual neck masses were made, and regression analyses for sex, age, clinical stage, chemotherapy, hyperthermia and boost was performed using CO regression model. Results : The residual neck masses of 77.5% NPC patients after radiotherapy resolved within three months. Univariate analyses revealed relationship between four factors: sex, age, N Stage, Chemotherapy and the time of residual neck masses resolving. M ultivariate analyses indicated that three factors: Sex, N stage, Chemotherapy were independent factors.lt was found that the time of residual neck masses resolving was positively associated with chemotherapy, while negatively associated with sex, age and N Stage. Conclusion : Most of residual neck masses in NPC patients after radiotherapy can resolve w ithin three months. Sex, N stage and chemotherapy were major factors leading to resolving of the residual masses.