Abstract: Investigations on tumor receptor imaging include the preparation of radioligands, in vitro assays and in vivo receptor imaging. Ligands for tumor receptor imaging has been labeled by ¹⁸F、¹²³I(or ¹³¹I)、¹¹¹In or ⁹⁹Tc^m. In vitro assays can be performed by radioligand binding, autoradiography and receptor identification. Tumor receptor imaging such as neuropeptide receptor imaging, steroid receptor imaging and sigma receptor imaging has been used for diagnosis, staging, therapy strategy and prognosis of a wide range of tumors, of which the most widely studied was neuropeptide receptor imaging.