Abstract: Abstract： Objective: To investigate the relationship between serum zinc concentration and recurrent apthous ulcer (RAU) and taste. Methods: From Jan 2013 to Jan 2014, forty patients of RAU were collected as the observation group. Meanwhile, 50 health examinees in our hospital were taken as the control group. The serum zinc concentration was determined by atomic absorption spectrophotometry，and a taste test for both group. Results: The serum zinc level of observation group was significantly lower than control group (P<0.01). The scores of taste test between observation group and control group was not statistically significant (P>0.05). The serum zinc level and the scores of taste test in males were higher than females in each group. Patients with MiRAU had a lower level of serum zinc than patients with MaRAU (P<0.05). The scores of taste test in patients with MiRAU were higher than that in patients with MaRAU (P<0.05). The Pearson correlational analyses showed serum levels of zinc have no relation with age (P>0.05), scores of taste test grows with age (P<0.05), serum zinc levels have no relation with taste scores (P>0.05). Conclusion：The cause of RAU has a relationship with zinc deficiency. The serum zinc level has no reference with taste.

Key words: recurrent apthous ulcer, zinc deficiency, hypogeusia