Objective To investigate the effect of telephone call follow-up on compliance with opening-mouth exercises among nasopharyngeal carcinoma(NPC)patients with radiotherapy-induced difficulty in opening mouth.Methods Sixty four nasopharyngeal carcinoma patients undergoing radiotherapy were randomized into control group(n=31)and observation group(n=31).The former group was given health education and instructions for functional exercises of opening mouth at discharge and regular return visits after discharge,and the observation group received regular telephone call follow-ups by an appointed nurse besides the same treatment as in the control group.The two groups were compared in regard to the compliance with the exercises of opening mouth and the incidences of difficulties in opening mouth at the first and second years after discharge. Results The compliance of the observation group was significantly higher that in the control group(P<0.01).The incidences of difficulties in opening mouth in the observation group were significantly smaller than that in those of the control at the first and second years after discharge(P<0.01). Conclusion Telephone call follow-ups are effective in the improvement of compliance of functional exercises in NPC patients with radiotherapy-induced difficulty in opening mouth,the reduction of the incidence of mouth-opening problems and the improvement of their quality of life.