Persistent human papillomavirus (HPV) infections is the single necessary cause of cervical cancer. Cervical cancer is still the major health problem in the developing countries. It has been the first rank women's cancer in Thailand for many decades. Approximately 10-20% of Thai women have the high-risk HPV (HR-HPV) infections in their cervices. This will frequently lead to low-grade squamous intraepithelial lesions (LSILs) (10%), high-grade squamous intraepithelial lesions (HSILs) (0.8%), and finally, cervical cancers (0.16%) within 10-20 years. The treatment options for LSILs are either observation or ablative surgery. However, in our institute, cryotherapy, which is the one of ablative surgery, is more frequently used to comfort our women. It is not only effective but safe with only minimal side effects; watery leukorrhea for 2-4 weeks, and local cervical infection not more than 1%. Contraindication to this procedure are active cervical infection, lesion of 2 mm-larger than probe, lesion inside cervical os and suspected cervical cancer. Additionally, in developing countries such as Thailand, this treatment is safe, acceptable, feasible and effective. Patients with LSILs could also have this treatment in some rural area from the 10-days trained nurses. Fortunately, recent reports showed that cryotherapy has abilities not only in clearing LSILs but also clearing the HPV infections, its necessary cause. However, there are no randomized controlled trial compared its clearing ability between observation and cryotherapy. Therefore, a randomized controlled trial is needed to demonstrate that. Findings from this trial will contribute enormously to older women who already get infected by HPV. Aside from preventing cervical cancer in treated woman, cryotherapy could also give her relief from worrying about having a time-bomb like HPV infection in her cervix.