Lactoferrin has been extensively studied over the past 70 years, and its many biological functions are widely accepted by the scientific community. It is not only involved in iron storage and transport, but also has anti⁃microbial, anti⁃oxidation, anti⁃tumor, regulation of immune system function, etc. It is widely regarded as a new antibacterial and anticancer substance. Studies have shown that the exogenous treatment of lactoferrin and its derivatives can effectively inhibit tumor growth and reduce the sensitivity of tumor occurrence. Lactoferrin plays an anti⁃tumor role mainly through cell membrane destruction, apoptosis induction, cell cycle arrest and cellular immune response. However, the underlying mechanisms of the antitumor effects of lactoferrin are not fully understood. This paper reviews the antitumor effects and mechanisms of lactoferrin and its derivatives. On the basis of these mechanisms, a new strategy for the anti⁃tumor effect of lactoferrin and/or its derivatives is proposed, and the potential of lactoferrin and its derivatives in the field of anti⁃tumor research is discussed.