The rise of CRISPR/Cas9 technology has driven the development of various fields of life science. With the continuous deepening of its understanding, people have made multiple improvements and optimizations to adapt to different application scenarios. The optimization of CRISPR/Cas9 technology has also brought many breakthroughs in the production of genetically modified mouse models. This article briefly reviews the development process of CRISPR/Cas9 technology, and summarizes optimization strategies at the level of CRISPR/Cas9 element optimization, construction of conditional knockout/knockin gene modified mouse models, and delivery systems for CRISPR/Cas9 elements and HDR templates. It looks forward to the future development of this technology.