Abstract： Objective To explore the depth of invasion of limbal tumors using in vivo confocal microscope and to compare the result to that in histopathological findings.Methods Five cases of limbal tumors with clinical diagnosis of squamous cell carcinoma were evaluated with in vivo confocal microscope.Tumor excision and lamella corneal transplantation were performed for each patient.The results of confocal microscopy were compared to that in histopathologic sections.Results One case of invasive squamous carcinoma,three cases of intraepithelial dysphasia and one case of squamous papilloma were identified by histopathological examination.The main pathological features could be recognized by confocal microscope images,including papillomatous hyperplasia,cytonuclear atypias,and activation of dendritic cells.Intersection of neoplasm and normal tissue could be displayed by oblique scanning.Conclusions With appropriated oblique scanning,in vivo confocal microscopy can provide information of cellular structure and the depth of invasion,this is useful in the diagnosis and management of limbal neoplasm.However,the identification of tumor cell phenotypes still needs ex vivo histopathological examination.