The aim of this study was to establish the expression and localization of E-cadherin and β-catenin inoral squamous cell carcinomas (OSCC) so that we could correlate the findings with prognostic-relevanthistopathological variables. E-cadherin and β-catenin expression in normal oral epithelia and in oral squamouscell carcinomas was examined immunohistochemically, and associations with histopathological differentiationand prognosis were then analyzed in 33 patients who had been operated on for OSCC. E-cadherin expressionwas found in (82%) of the squamous cells of well differentiated OSCC, (61%) of moderately differentiatedand (39%) of poorly differentiated. E-cadherin expression was significantly associated with histological grade(p=0.000). No nuclear staining was detected. In (19.5%) of the cells E-cadherin localized in the cytoplasm, withno correlation to the histological grade (p=0.106). β-Catenin expression was found in 87% of the squamous cellsof well differentiated OSCC, 67% of moderately differentiated and 43% of poorly differentiated, the expressionwas significantly associated with histological grade (p=0.000). the nuclear β-Catenin expression appeared in 3.3%of the cells and it was correlated to the histological grade (p=0.000). In (23.5%) of the cells β-Catenin localizedin the cytoplasm, with correlation to the histological grade (p=0.002). According to this study the expression ofβ-catenin and E-cadherin were independent prognostic factors for histological grade. E-cadherin was closelylinked to β-catenin expression in OSCC (p=0.000) and to tumor differentiation. That reflects a structuralassociation and the role of both in tumor progression.