Cervical intraepithelial neoplasia (CIN) II, III is a preinvasive stage of squamous cell carcinoma of the uterine cervix. The standard treatment for CIN II, III consists of ablation and excision. However, nonsurgical treatment may be necessary for some women to preserve future reproductive potential. This review was conducted to summarize available published data on the efficacy and safety of medical treatment for CIN II, III. Based on existing studies, cyclooxygenase (COX)-2 inhibitors; indole-3-carbinol; and novel immunotherapy agents, including ZYC101a, MVA E2, and HspE7, have been observed as possessing therapeutic activity without any major treatment-related complications. These promising results provide important data for the future direction of clinical research.