The aim of this study is to reveal the altered expression of E- and, P-cadherin, α- and β-catenin in cervical squamous cell carcinoma progression from dysplastic lesions lesion to invasive squamous cell carcinoma. Immunohistochemical method was used in 25 L-SIL (CIN I), 25 H-SIL (CIN II-III) and 30 invasive squamous cell carcinomas (SCC). Ecadherin was detected in 91.7%, 41.7%, 6.9% of L-SIL, HSIL and invasive squamous cell carcinomas, respectively. The difference between L-SIL, H-SIL and SCC was statistically significant (p=0.0001). The expression of P-cadherin and α-catenin was reduced significantly (p=0.009 for Pcadherin, p= 0.0001 for α-catenin). β-catenin expression was revealed in all lesions with nearly the same frequency. Loss of adhesion proteins, E-cadherin, P-cadherin and α- catenin is observed in cervical squamous cell carcinoma progression. The presence of β-catenin in H-SIL and invasive carcinomas might suggest its role in tumor progression by its effect in Wnt signaling pathway in cervical carcinomas. [Turk J Cancer 2006;36(2):64-68].