To compare the characteristics of the chronic constriction injury model in SD rats inducedby Minor and classic CCI, and to provide a reference for the experimental design of basic research. Methods Eighteen 8-week-old SD male rats were randomly divided into sham, Minor CCI, and classic CCI groups with six animals in eachgroup. The 1-ligature was ligated on the sciatic nerve in the Minor CCI group, and the 4-ligature was ligated in the classicCCI group. Animals in the three groups were examined before modeling and at 7, 14, 21 and 28 days after modeling for themechanical withdrawal threshold, thermal withdrawal latency, and accumulated pain score. Ultrastructural changes of thesciatic nerve were observed by electron microscopy. Results Nociceptive symptoms of Minor and classic CCI groups were the same in terms of the mechanical withdrawal threshold and thermal withdrawal latency. Additionally, the accumulated pain score of the Minor CCI group was lower than that of the classic CCI group. Ultrastructural changes of the sciatic nerve in Minor and classic CCI groups were the same. Both of them showed destruction and disintegration of the myelin structure, formation of myelin spheres and autophagosomes. Conclusions The Minor CCI model is more stable and nociceptive symptoms can be maintained for up to 28 days after modeling, basically without self-mutilation, which is suitable for shortterm experimental design and minimizes the pain of experimental animals. The classic CCI model has long-lasting nociceptive symptoms that remain in the plateau period for 28 days after modeling, but the self-mutilation phenomenon is obvious, which is suitable for medium and long-term experimental designs.