Positron emission tomography-computed tomography (PET-CT), which is among the methods used for oncologic imaging in today's health sector, is used for staging, detection of recurrence and evaluation of response to treatment of many cancer types. However, 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG), which is used as a cancer imaging agent in nowadays, can lose its selectivity and sensitivity when increased glucose consumption such as inflammation and infection . Therefore, the development of new cancer cell recognition agents has become inevitable. Peptides have been used for imaging by binding to receptors of cancer cells because of its high sensitivity and selectivity to cancer cell . In this study, three specific peptides were suggested to the cancer receptor (hFOLR1α) by "Computer-aided ligand discovery and design" (CADD) method. The proposed peptides were synthesized by the Solid-Phase Peptide Synthesis method, purified by HPLC with acetone-water phase and then characterized by LC-MS. The ITC (Isothermal Titration Calorimetry) was determined by the affinity of the peptides to the target receptor. In vitro stability tests were performed by HPLC.