The oral cancer development can be from apparently normal mucosa, or from precursory lesions, that can represent different step of oral epithelial carcinogenesis process. This study aimed to analyze morphologically trough the hematoxilina/eosine technique normal oral mucosa, oral fibroepithelial inflammatory hyperplasia and oral epithelial dysplasia (OED) to get more informations about the epithelial alterations that can to precede the installation and evolution of oral cancer. Its was observed that some of the morphologic alterations in the oral fibroepitelial hyperplasia were provably associated to the inflammatory process, where exist the action of chemical mediators with capacity to promote cellular morphologic modifications and alterations of the tissue architecture but not to common alterations of lesions potentially malignant. Correlating the clinical aspect of the lesions with the histopatologic diagnosis of oral epithelial dysplasia its was not observed expressive difference, however the majority of the OED specimens had clinical diagnosis of leucoplasia. Its was concluded that the simple observation of the morphologic characteristics of epithelial alterations in the oral mucosa can to improve the diagnostic of the lesions suffered by this mucosa, however, its not offers much informations about which would be the events that would lead to the establishment of a determined lesion.