The aim of this retrospective study was to investigate the frequency of different types of oral lesions in biopsies sent to a department of human oral pathology for histologic examination. The impact of gender, age, and breed was assessed. The biopsy specimens were reviewed and diagnosed according to human pathology nomenclature and the classification of different diagnoses used in human and veterinary pathology is discussed. Reactive lesions were diagnosed in 39 % of the biopsies, while benign and malignant neoplasms were diagnosed in 27 %, and 15 % of the biopsies, respectively. The most common diagnosis was reactive gingival hyperplasia (24 %), followed by peripheral odontogenic fibroma (21 %) and melanoma (8 %). Epulides comprised 69 % of all lesions. Dogs with malignant oral tumors were older than those with benign tumors, however there was no significant gender differences for any group of lesions Pure-bred dogs were more prone to develop pathology than mixed-breeds. Of the larger breeds in Sweden, Boxer dogs had the highest prevalence (3.77/1000) of biopsies submitted.