The development of carcinoma is associated with alterations in the expression of many cell adhesion molecules. Syndecan-1 is a cell surface proteoglycan that binds cells to the extracellular matrix and changes its expression following malignant transformation in some tumors. Our purpose was to examine the pattern of syndecan-1 expression in cancer of the uterine cervix and assess the clinicopathological significance of syndecan-1 expression. A total of 106 tissue specimens (6 normal, 19 cervical intraepithelial neoplasia (CIN) and 81 invasive cancer) were analyzed immunohistochemically. In addition, the corresponding expression of mRNA in tumor tissues was evaluated by reverse transcription-polymerase chain reaction (RT/PCR) in comparison with normal counterparts. Syndecan-1 was positive in normal squamous cells except the basal cell layer. The intensity of syndecan-1 staining was the strongest in normal epithelium, followed by CIN, and invasive squamous cell carcinoma. Syndecan-1 expression in cancer tissue tended to be higher in keratinizing type than non-keratinizing type and not found in adenocarcinoma. Syndecan-1 expression was markedly decreased at the mRNA level in invasive squamous cell carcinoma as compared with that of normal uterine cervix. Interestingy, there was an inverse correlation between the expression of syndecan-1 in the primary site and lymph node metastasis, although there was no significant correlation between syndecan-1 expression and the prognosis. The results of the present study suggest that syndecan-1 expression is associated with squamous tissues and plays a key role in the progression of the cancer of the uterine cervix especially in the metastatic process.