The need for studies on prevalence of lesions in the field of oral medicine increases as more patients suffer from oral mucosal diseases. Data on prevalence of oral mucosal diseases throughout the world are scarce. Therefore, we have made a retrospective study of patients referred to the Department of Oral Medicine, University of Zagreb, during a period of one year, i.e. 2010. Data on patient age, gender and diagnosis were recorded. Out of 1118 analyzed clinical records of the patients, 756 (67.6%) were women and 362 (32.4%) were men. The age range of female patients was 54 +/- 19 years (mean age 62.17 years) and the male age range was 49+/-21 (mean age 64.17 years). The most common diagnosis was burning mouth syndrome (23.4%), followed by xerostomia (10.6%), traumatic ulceration (8.7%), geographic tongue (6.6%) and denture stomatitis (5.7%). Other diagnoses were found in a smaller percentage. Our results point out an increased need for oral medicine services.