BACKGROUND Salivary glands tumors are relatively uncommon neoplasm with widely variable histopathologic and biologic characteristics. Alteration in some proto-oncogenes and tumor suppressor genes may lead to the development and progression of these tumors. AIMS The purpose of this study was to analyze the immunohistochemical expression of P(53) and bcl-2 in some salivary gland tumors in relation to tumor size, histologic grade, and extent of invasion. SETTING AND DESIGN The sample consisted of 22 formalin-fixed paraffin embedded blocks of benign and malignant salivary glands tumors. MATERIAL AND METHOD P(53) and bcl-2 immunoreactivity was semi-quantitatively evaluated in at least 1000 cells examined under the microscope at 40x magnification and recorded as percentage of P(53) or bcl-2 positive tumor cells over the total number of cells examined in the same area. Percentage scores were subsequently categorized using the 5% cut-off point for positive staining. RESULTS AND CONCLUSION Pleomorphic adenoma (PA) showed negative expression of P(53) and bcl-2 in 70% of cases, whereas all malignant salivary glands tumors were positive for P(53) and bcl-2. P(53) positive/bcl-2 positive immunostaining reaction was week in small size PA and was totally absent in larger lesions. However, all malignant tumors expressed P(53), with the highest record in low-grade adenocarcinoma (76%) and the lowest score was observed in both low-grade carcinoma in PA and adenocystic carcinoma. bcl-2 immunostaining was also assessed, the highest recorded score was in high-grade adeno cystic carcinoma (90%) and the lowest in both low-grade carcinoma ex-PA and low-grade cystic mucoepidermoid carcinoma (3%). P(53)/bcl-2 immunostaining reactivity could be helpful in demonstrating salivary glands tumor behavior in terms of progression and extent of invasion.