Abstract: The abnormal expression (level and status) of the key molecular targets of tumors is related to molecular targeted therapy response, effect, and prognosis. Therefore, the expression level and status of key molecular targets of tumors must be accurately evalu -ated, regardless of the status before, during, and after receiving targeted therapy. Molecular imaging is a non- invasive method used for qualitative and quantitative research on key molecular targets of tumor in vivo and in real-time. This technique is also employed to screen treatment beneficiaries, guide therapy, and evaluate prognosis. This paper reviews the application progress of molecular imag -ing using various probes in cancer targeted therapy. The clinical value of molecular imaging in tumor targeted therapy is further analyzed to promote the development of novel targeted therapy for tumors.