Up‐regulated TYMS by hsa‐miR‐99a and down‐regulated SASH1 by hsa‐miR‐21 were detected in CIN versus N and CIN versus CSCC in our study, indicating its important role in CIN, and up‐regulated TYMS and down‐regulated SASH1 might serve as a biomarker for CIN and the progression of CIN into CSCC. The gene discussed is TYMS; the disease is cervical squamous intraepithelial neoplasia.