The aim of this study was to evaluate the expressions of oncoproteins and to correlate the results with clinicopathologic parameters in papillary thyroid carcinoma (PTC). Papillary thyroid cancer (PTC) is the most common form and accounts for about 80% of all thyroid cancers. Although PTC generally has a good prognosis, some patients suffer from local recurrence and/or distant metastasis. Oncogenes have reported to be related not only in carcinogenesis but also in tumor prognosis, tumor type, differentiation and site of tumor in epithelial malignant tumors such as thyroid, breast, ovarian, and stomach cancer. This study was planned retrospectively and was performed in 87 patients (47 PTC, 40 benign lesions). The data of clinicopathologic parameters and tissue samples were collected from the archives. Sections stained with H&E were evaluated for each case and after confirming the diagnosis of PTC, oncoprotein expressions were determined by immunohistochemical analysis. The differences of oncoprotein expressions in PTC compared with control group were statistically significant. Cyclin D1 and p53 expressions were significantly increased in PTC. The expressions of bcl-2 and c-erbB-2 in PTC were found as increased, but the correlation between these proteins and poor prognostic parameters were not significant. We suggest that increased expressions of cyclin D1 and p53 could be used as prognostic factors in patients with PTC.