Uterine cervical excision is commonly performed at women with child-bearing age and considered as a major risk factor for spontaneous preterm birth although infection is known as a single most causative factor. Research animal models are essential to elucidate the mechanism of preterm birth. However, known infection-based preterm birth animal models have relatively low rate of preterm birth as well as high rate of maternal death. We aimed to develop a more efficient and safe animal model by cervical excision using female rodents. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (2014R1A1A1002300). All animal experiments were approved by the Committee for the Care and Use of Laboratory Animals at Korea University (KUIACUC-2015-117). Sexually mature female Sprague-Dawley rats were used for comparison of usefulness and safety between abdominal and vaginal cervical excision, evaluation of histologic recovery according to extent of cervical excision and pregnancy rate after different post-excision recovery periods. Sexually mature female C57BL/6 mice were used for investigating optimal preterm birth conditions using cervical excision and lipopolysaccharide (LPS) administration. Gestational period was calculated by setting “mucus plug detection day” to day 1. All data were statistically analyzed. Vaginal excision of the cervix was faster and safer than abdominal excision. Final cervical length after different extent of cervical excision was dependent on initial extent of cervical excision. Optimal time of mating for conception was about three weeks after cervical excision. Rates of preterm birth were 0%, 30%, 60%, and 100% in control, cervical excision, LPS injection, and cervical excision plus LPS injection groups, respectively. With regard to pups, cervical excision plus LPS group had a lower number and weight. However, maternal and fetal survival rates were higher in the cervical excision plus LPS model than one in previously known higher dose LPS model. Our novel cervical excision plus LPS preterm birth mouse model would be optimal regarding efficacy, safety, and cost-effectiveness for research of spontaneous preterm birth. Researchers will be able to use this animal model for basic studies related with preterm birth.