Objective: The aim of the study was to assess the diagnostic value of pap smears and detection of the p16 and Ki67 proteins in women with cervical intraepithelial neoplasia (CIN). Materials and method: 630 women, aged between 25 and 65, with abnormal pap smears were included into the study. All patients had a control pap smear and in each case punch biopsy with endocervical curettage were performed under the control of a colposcope. The presence of p16 and Ki67 proteins was detected using the CINtecPlus test. The results of the research were statistically assessed. Results: Abnormal pap smears were found in 82.5% (520/630) of the studied women. In 40% (252/630) of the cases the LSIL changes were found. The recognition of ASC-US concerned 35.2% (222/630) of the patients, and pap smears with the HSIL result were found in 7.3% (46/630) of the women. In 17.5% (110/630) of the patients the result of the cytological examination was normal. Abnormal results of the pap smears were found significantly statistically more frequently (p<0,0001) in women with cervical intraepithelial neoplasia (CIN). The results of the CINtecPlus test were positive in 68,4% of women with CIN and in 33,3% of patients with normal cervix. In the group of women with precancerous lesions (HGSIL/CIN2+) the diagnostic accuracy of the pap smear was 41% for the cytological results ASC-US, 56% LSIL and 73% for detection of HSIL. Immunocytochemical detection of p16 and Ki67 proteins gained the highest accuracy (78%) in recognition of cervical precancerous lesions. Conclusion: 1. ASC-US and LSIL cytological recognition has low accuracy in the diagnosis of CIN2+ cervical changes. 2. Cytological recognition of HSIL has the highest accuracy in the diagnosis of CIN2+ changes. 3. Immunocytochemical detection of p16 and Ki67 proteins is more accurate in recognizing precancerous states and cervical cancer than cytological examination. 4. Immunocytochemical detection of the p16 and Ki67 proteins can be used to triage patients with atypical squamous cells of undetermined significance and low grade squamous intraepithelial lesions.