Metastasis is the main cause of poor prognosis of malignant tumors.The prevention and treatment of tumor metastasis are still challenging and a bottleneck that has yet to be broken for all countries.The efficacy of traditional Chinese medicine(TCM) in the prevention and treatment of tumor metastasis has been recognized.Professor Tian Jianhui's theory of “deficiency of vital Qi and hidden toxicity”，which is the core pathogenesis of tumor metastasis，provides innovative ideas for exploring the key issues of clinical tumor metastasis.However，at present，the target of “deficiency of vital Qi and hidden toxicity” related to tumor metastasis still needs to be further deciphered，and the backwardness of the TCM dosage form，poor solubility of the active components，lack of targeting，and toxic side effects have limited the clinical application.In recent years，the rapid development of nanotechnology and the emerging cross-cutting field of nanomedicine have brought new hope for TCM to prevent and treat tumor metastasis.Nanomaterials can be used to prepare efficient drug delivery systems due to their good biocompatibility，tumor targeting，intelligent responsive controlled release，and anti-multidrug resistance.In addition，nanomaterials show great potential in the field of tumor metastasis prevention and treatment due to their unique optical，acoustic，electrical，thermal，magnetic，enzymatic，or enzyme-like activities，which can give full play to the advantages and features of drug-adjuvant integration.