Because no simple and precise method is available to test intensity of the reaction resulted from a nasal provocative test in diagnosis of nasal allergy, comparisons were made among the conventional test methods of rhinoscopy (RS), rhinomanometry (RM) and the carbon powder elimination test (CET) devised by the authors. The rhinoscopy shows high positive rates and has advantages being free from any special equipment, prolonged time or the patients' cooperation, but also had disadvantages such as requirement of skill of examiner and problems in objectivity. The carbon powder elimination test is a preferable method in that it is not only equipped with the advantages of the rhinoscopy but also makes up for its disadvantages, but a disadvantage of CET is requirement of longer time than RS. Rhinomanometry had lower positive rates and requires a special equipment, prolonged time and the skillful patients' cooperation. The disadvantage is that its impracticableness in many patients--26% impracticableness even in adult patients, but the method is fully objective. From these findings the value of Carbon Powder Elimination Test in judging provoked reactions is recognized.