At the beginning of the 2015, US president Obama launched the program of "Precision Medicine". Interpretation of "Precision Medicine" provided better understanding of diseases by combining present structure of medicine and the concept of individualization, leading to the expansion of knowledge through three dimensions: time-space-subject. Recently, gene technology pushed the treatment of cancer forward, gene as well as molecular typing resulted in entirely new comprehension of cancer, and target drug opened a new era of cancer treatment. Until now, however, the overall survival of malignancies (eg. carcinoma of pancreas, liver and lung) remains. "Precision Medicine" brought in revolution of disease classification system, and diagnosis of certain rare or inherited diseases. Huge amount of data were supplied by gene sequencing, which improve the research and application of new drug. With these advances, the clinical application of "Precision Medicine" still confronts numerous challenges, nearly all current guidelines are based on population data rather than personalized characteristics. With the integration of past and present, there is a long way to go for "Precision Medicine".