Objective To adopt a criterion summarized in long-term practice to judge the immune status of recurrent aphthous ulceration（RAU）patients, and to analyze its rationality and feasibility. Methods 60 cases were included, whose clinical information, such as age, sex, constitution status, history of system diseases and severity of ulceration were collected. The subjective judgement results of the immune status were obtained according to the criterion summarized in clinical practice. At the same time, peripheral blood parameters about immune function were examined in order to obtain the objective examination results of the immune status. With the examination result as the gold standard, the rationality of the criterion was estimated through its sensitivity and specificity. Results According to subjective judgment, there were 86.67% cases with abnormal immune status（28.33% cases with elevated immune status, and 58.33% cases with reduced immune status）. According to objective examination, there were 93.33% cases with abnormal immune status(23.33% cases with elevated immune status, and 70.00% cases with reduced immune status. Sensitivity and specificity were 89.29% and 50.00% when the criterion was used to judge immune abnormality, 42.86% and 76.09% when the criterion was used to judge immune elevation, and 64.29% and 55.56% when the criterion was used to judge immune reduction. Conclusion It is of some rationality and feasibility to judge the immune status according to the criterion based on clinical information，and the criterion can be used in small clinics.
