Pharyngeal cancer is often accompanied by serious functional disorders due to patients' anatomical characteristics. Nonetheless, most pharyngeal cancer patients undergo radiotherapy with good treatment results. However, their reactions to adverse event are commonly seen in the treatment process, and the resulting pain that occurs is extremely uncomfortable for them. This study investigated the outbreak situation of the adverse events (radiation dermatitis, dysphagia, throat) of 37 pharyngeal cancer patients (35 men, 2 women) who received radiotherapy. It also looked at their changes in radiation dermatitis using CTCAEv4.0 and the use time of the steroid ointment that helped treat their symptoms. The adverse events mentioned above appeared in most cases. For radiation dermatitis, the progression of the disease severity of the adverse event varied among individuals, but a similar tendency was seen in outbreak time and progress. In addition, there was the use time of the steroid ointment for the symptom in the range of 25.2Gy–63.0Gy (median; 45.0Gy) with a total dose of radioactivity. We think that the evaluation of the adverse event using a periodical patient interview was effective in grasping individual correspondence and the degree of the adverse event. For future studies, it is suggested that patient interviews and a review of the rating system will help effectively evaluate the adverse events of patient undergoing radiotherapy.