Abstract: Objective: To observe the expression of P16, CyclinD1, and PTEN, to determine the significance of thisexpression, and to report abnormal DNA ploidy in squamous cervical cancer. Methods: A total of 123 specimens includ-ing 82 specimens of invasive cervical carcinoma (ICC), 22 specimens of cervical intraepithelial neoplasia (CIN) and 19specimens of normal cervical (NC) tissues were analyzed by SP immunohistochemistry. Flow cytometry was used to detectthe expression of P16, CyclinD1, and PTEN as well as abnormal DNA ploidy. Results: The expression rates of P16,Cy-clinD1, PTEN, and abnormal DNA ploidy in NC, CIN, and ICC were 10.53%, 40.91%, 57.32%, and 100%; 68.18%,39.02%, 21.05%, and 50%; and 60.98%, 0%, 27.27%, and 73.17%, respectively. These results suggest that as cancerstage increases, P16 expression, CyclinD1 expression, and presence of an abnormal ploidy number increase graduallywhile PTEN expression decreased gradually. P16 expression was correlated with clinical stage, pathological grade, lymphnode metastasis and tumor size. PTEN expression was correlated with clinical stage, lymph node metastasis and tumor size.CyclinD1 expression was correlated with clinical stage and lymph node metastasis. Abnormal DNA ploidy was not corre-lated with the clinical or pathological parameters of ICC. Conclusion: The abnormal expression of P16, CycinD1, and PTEN along with abnormal DNA ploidy can influence cell cycle. These parameters can also be used in combination asmarkers for ICC diagnosis and as targets for ICC treatment.