Abstract: With the rapid development of emerging biotechnologies such as high-throughput sequencing, multi-omics and multi-dimensional research models for biological big data have been initiated. Concurrently, the fast-evolving technologies including mathematical modeling, artificial intelligence, cloud computing, blockchain, big data, the Internet of Things, and 5G have enabled the development of digital twin. Digital twin, a model mapping of physical objects, processes, and systems in digital space, has shown great potential in the medical field. Digital twin technology can provide visualized 3D structures for human organs and systems to assist diagnosis and treatment, create a tangible "skeleton" for data mining in genomics, metabolomics, and phenomics, and simulate processes for chronic disease management, drug development, and clinical trials, thereby advancing the medical field. The aim of the article, therefore, is to review the methods and applications of digital twin in the medical field, with the hope of providing reference for the development of medical digital twin research in China.