Neurotrophin-tyrosine kinase receptor (NT-Trk) signaling pathway plays an important role in the neural regulation of development. Now it has been recently revealed that Trk may also participate in the pathogenesis of many malignant tumors. It is demonstrated that the expression of TrkB is related to oncogenesis. The activation of brain-derived neurotrophic factor (BDNF)/TrkB signal transduction pathway stimulates tumor cell survival and angiogenesis, and contributes to the resistance to cytotoxic drugs and anoikis. The role of TrkB signal transduction pathway in tumors is reviewed in this paper.