The aim of this study is to determine the incorporations of PHT radiolabeled with I-131 (I-131-PHT) on U-87 MG, Daoy and A549 cancerous cell lines. For this, cold and radio-labeling studies were carried out. The radio-labeling yield of I-131-PHT was obtained about 95 %. Subsequently, cell culture studies were carried out and radio-labeling yields of I-131, I-131-PHT on U-87 MG, Daoy and A549 cancerous cells were investigated. Cell culture studies demonstrated that the incorporation values of (IPHT)-I-131 on the three cell lines decreased with increasing radioactivity. Consequently, I-131-PHT may be a good radiopharmaceutical for targeting radionuclide therapy of Central Nervous System Tumors.