Background & Objectives: cervical dysplasia indicates the growth disorder of cervix and is characterized by the appearance of cancerous and precancerous cells in cervix. Cervical dysplasia often has no symptoms but can progress to cervical cancer in 5 % of the cases. Early diagnosis of these pre-invasive lesions with pap smear can prevent, to a great extent, the progress of lesion to cancer. The prevalence of cervical dysplasia is different in different parts of the world and depents, to a great extent, on its etiology. This study was an attempt to determine the prevalence and types of cervical dysplasia in 5000 cases of pap smears.

 Methods: This descriptive cross-sectional study was conducted on 5000 cases of pap smears selected randomly from among 8249 pap smears in the period between March 2003 to August 2004. Some samples were studied retrospectively and some others prospectively. The population of the study was composed of women referring to Ardabil health care centers for pop smear test. The data were collected with questionnaires and were analyzed using SPSS software (ver.11).

 Results: Cervical dysplasia was found in 56 cases (1.12%) 0.66% of which was CIN I, 0.3% CIN II and 0.16% CIN III.

 Conclusion: The total percentage of cervical displasia in this study was 1.12%. This prevalence in other similar studies varies between 0.4% in Scotland and 12% in USA. Nevertheless, the prevalence found in this study is in line with most of the similar researches.