The main research achievements of functional mechanism,efficacy and safety of targeted drugs in metastatic colorectal cancer were reviewed in this paper for looking forward to the future development direction. Bevacizumab has remarkable curative effect in anti-angiogenesis drugs; curative effect of small molecule drug is worth expecting. Indications of drugs on the resistance to EGFR signaling pathway will be more accurate; the research of molecular markers such as BRAF,HER2 and PI3KCA further promote the development of the precision medicine. The researches on PD-1/PD-L1 in immune targeted drugs made a breakthrough in metastatic colorectal cancer. In the future under the guidance of molecular markers,precision medicine in metastatic colorectal cancer is more worth expecting than before.