In order to investigate the pathogenesis of pharyngeal allergy clinical studies were performed in 97 cases of nasal allergy and in 57 cases of cryptomeria pollinosis. They were divided into two groups depending on whether accompanying laryngopharyngeal symptoms were present. The results were as follows: Laryngopharyngeal symptoms were observed in 43.3% of nasal allergy cases. The sensory symptoms, namely an irritable sensation in the pharynx, were particularly severe, compared with respiratory symptoms. The sensory symptoms were mainly localized in the nasopharynx. The findings showed granular pharyngitis as well as lateral pharyngitis in many cases, such as redness and swelling of lymphatic nodules. When 1000 times diluted HD solution was experimentally and directly applied to the nasopharynx of 8 patients of HD positive nasal allergy, similar pharyngeal findings were observed and radiocephalogram revealed a diffuse swelling of the mucosal membrane covering the nasopharynx to the posterior pharyngeal wall. Laryngopharyngeal symptoms were seen in female patients slightly more than in male. Nasal symptoms were mostly found in cases having “severe sneezing” and “watery rhinorrhea”. Nasal allergy was seasonal rather than perenial and the major causal antigen was pollen. Nasal cytology revealed a high appearance rate of eosinocyte and eosinocytes were singly observed in many cases rather than the mixed type with neutrocytes. The appearance of basocytes was higher in patients with laryngopharyngeal symptoms. Blood eosinocyte as well as lymphocyte level was higher in patients-with laryngopharyngeal symptoms. IgE tended to be slightly higher in patients with laryngopharyngeal symptoms and IgG as well as IgA was also somewhat high in patients with them. IgM, however, showed almost no difference in those patients with or without laryngopharyngeal symptoms. Histamine pexic ability was low in those with laryngopharyngeal symptoms. The authors determined compliment CHSO in cases of cryptomeria pollinosis. It was found low for one to two weeks after the onset of the pollinosis and thereafter it gradually rose. However, the variation seemed to be large in those who have laryngopharyngeal symptoms. Lymphatic nodules were also histologically studied in 12 cases of pollinosis. Specifically marked lymphatic infiltration was observed in subepithelial layer and interstitial connective tissue, but only an eosinocyte was found in several fields of optical microscopic view. In this regard, lymphatic nodules seemed somewhat different from the nasal mucous membrane. The same findings were obtained in the lesion experimentally induced to lymphatic nodules by HD solution. As described above, it was concluded that the onset of laryngopharyngeal symptoms was induced by an extensive and direct contact of antigen to pharyngeal mucous membrane for a short period of time. Thus, it was considered that type I allergic pathogenesis was modified by the strong reaction of the lymphatic epithelial system. The authors also roentgenologically measured the size of pharyngeal tonsil in patients of asthma and of nasal allergy. The results were as follows: the pharyngeal tonsil of the former was small and that of the latter large, compared with healthy children. Finally, the necessity to make furthermore study of pharyngeal allergy was emphasized under the consideration to the reaction of the pharyngolymphatic epithelial system.