A 42-year-old-man with a history of Japanese cedar pollinosis repeatedly visited the emergency clinic due to dyspnea during the season of Japanese cedar pollen dispersion. Before each onset of this symptom, he had always drunk tomato juice. Swelling of the oral and nasal mucosa, and congestion of the bulbar conjuctiva was observed. No audible wheezing was present. His pulmonary function test results were normal (FEV1.0=4.02 L, %FEV1.0-124%, negative reversible test). The CAP RAST scores were 4 for tomatoes and 3 for Japanese cedar pollen. A result was obtained in a challenge test using tomato juice. Since tomato juice was involved in the development of the symptoms, a diagnosis of oral allergy syndrome induced by tomato juice was made. When tomato juice consumption was avoided, no symptoms developed. A common antigenicity was found between tomatoes and Japanese cedar pollen. This may be associated with the development of this allergy during the dispersion season of Japanese cedar pollen. The dyspnea may have reflected a feeling of pharyngeal narrowing which is a symptom of oral allergy syndrome. The possibility of oral allergy syndrome as the chief complaint should be considered also in patients with dyspnea. This is the first reported case of oral allergy syndrome induced by tomato juice.