[en] Objective: To evaluate the automatic synthesis of ¹⁸F-labeled cyclic RGD peptide c(RGDyK)and its biological distribution in the tumor-bearing mice. Methods: N-succinimidyl-4-¹⁸F-fluorobenzoate (¹⁸F-SFB) was automatically synthesized and then re-dissolved in acetonitrile (MeCN). The cyclic RGD peptide c(RGDyK) was mixed with an hydrous DMSO and N, N-diisopropyl ethylamine (DIPEA). ¹⁸F-FBRGD was obtained by the reaction of peptide solution with 18 F-SFB. The final product was purified by HPLC gradient separation system and solid-phase extraction method. The biodistribution study and competition test of N-4-¹⁸F-fluorobenzoyl-RGD (¹⁸F-FB-RGD) in the tumor-bearing mice was performed. Results: The labeling yield of ¹⁸F-FB-RGD was (33.6±3.5)%. The synthesis time was 110 min. The radiochemical purity was more than 98%. The tumor uptake of ¹⁸F-FB-RGD was (3.43±0.15), (2.61±0.14), (2.11±0.13), and (1.79±0.18) %ID/g, respectively, at 30, 60, 90 and 120 min after injection. The ratio of tumor to muscle activity ranged from 4.26±0.69 to 5.80±0.78. The tumor uptake decreased dramatically after RGD blockage. The uptake was (0.46±0.21) %ID/g and (2.87±0.59) %ID/g in the blocked and unblocked mice, respectively, at 60 min after blockage. Conclusions: ¹⁸F-FB-RGD can be automatically synthesized and it may become a promising tumor imaging agent. (authors)