Objective: It is known that a region of epithelial dysplasia cannot easily be distinguished macroscopically from normal looking area surrounding early oral squamous cell carcinoma (OSCC).For detecting surgical margin, we often use vital staining method with iodine (IS) in Japan because IS can delineate the extent of lesions.However it is one of the most serious problems that iodine sometime causes allergic reactions in humans.In North America, they say that fluorescence visualization (FV, VELscope(R)) is useful tool for detecting oral epithelial dysplasia as a precancerous lesion in recent years.The aim of this study is that we clarify the useful of FV and we investigated clinico-pathological analysis between IS and FV.