A clinical study of 107 patients with nasal allergies who were treated at Kushiro General Hospital between April 1998 and March 2000 was performed. Radioallergosorbent tests (RAST), X-rays, and nasal smears for the detection of eosinophilia were performed to obtain a diagnosis of nasal allergy. The patients (50 males, 57 females) ranged in age from 3 to 71 years. The RAST was positive for timothy in 22.4% of the patients, 14.0% for birch and 12.1% for mugwort. The most common pollinosis allergen in the Kushiro area was grass pollen. Other pollinosis allergens were birch pollen and mugwort pollen. We measured the daily count of dispersed birch pollen and timothy pollen in Kushiro and Sapporo. Birch pollen and timothy pollen was dispersed earlier in Kushiro than in Sapporo. Nasal allergies in the Kushiro area appear to be related to local characteristics, such as climate and geographical features.