Introduction: According to the prevalence of sore mouth, its outcome and possible role of anemia in its etiology and some contradictions in this theory, our study was performed to evaluate the role of iron deficiency anemia as a etiological factor for sore mouth. Materials and Methods: This historical cohort study was performed on 40 cases, including 20 anemic patients as the experimental group and 20 healthy individuals as the control group with similarity in socio economical, sex and age factors. Oral examination was carried out in two groups to evaluate soremouth presentations including atrophic glossitis, recurrent oral ulceration, pale oral mucosa, tongue burning sensation, glossodynia and angular cheilitis. Data was analyzed by chi-square test. Attributable risk (AR) and related risk (RR) were calculated. Results: Out of 40 studied cases, sore mouth manifestations were found in (45%) of individuals in case and (5%) control groups (p<0.005). Regarding the anemic patients, RR and AR of sore mouth were 9 and 40% respectively. The most prevalent manifestations of sore mouth were atrophic glossitis, recurrent oral ulceration, pale oral mucosa, tongue burning sensation, glossodynia and angular cheilitis. Conclusion: According to this study, it seems iron deficiency anemia has a significant role in sore mouth incidence. Evaluation of anemia treatment effect on sore mouth elimination is recommended.