Background: To manipulate particular locations in the bacterial genome, researchers have recently resorted to a group of unique sequences in bacterial genomes that are responsible for safeguarding bacteria against bacteriophages. Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9) are two such systems, each of which consists of an RNA component and an enzyme component.Methods and Results: This review focuses primarily on how CRISPR/Cas9 technology can be used to make models to study human diseases in mice. Creating RNA molecules that direct endonucleases to a speci c position in the genome are crucial for achieving a speci c genetic modi cation. CRISPR/Cas9 technology has allowed scientists to edit the genome with greater precision than ever before. Researchers can use knock-in and knock-out methods to model human diseases like Neurological, cardiovascular disease, and cancer.Conclusions: In terms of developing innovative methods to discover ailments for diseases/disorders, improved CRISPR/Cas9 technology will provide easier access to valuable novel animal models.