Objective To prepare 18F-FP-CIT, a PET probe targeting dopamine transporter (DAT), using the Allin One radiopharmaceutical synthesis module, and evaluate its stability, synthetic efficiency, and clinical application value in Parkinson's disease (PD) and atypical Parkinsonism syndromes (APS). Methods A retrospective analysis was performed on 21 patients with clinically suspected PD or APS at The First Affiliated Hospital of University of Science and Technology of China from November 2022 to August 2025.18F-FP-CIT was synthesized using N-(3′-methylsulfonyloxypropyl)-2β-carbomethoxy-3β-(4′-iodophenyl) nortropane as the precursor, via fluorination catalyzed by tetrabutylammonium hydroxide and amino polyether (Kryptofix2.2.2), followed by purification and quality control.18F-FP-CIT PET/CT scans were performed on 21 patients to observe DAT distribution changes in the bilateral striatum, including the bilateral caudate nuclei, anterior putamen, and posterior putamen. Results After optimizing the reaction conditions, the synthesis time of 18F-FP-CIT was (60.4±1.01) minutes, and the radiochemical yield was (31.6±3.05)%. All patients showed significantly decreased or absent DAT uptake in the bilateral posterior putamen, with more obvious injury on the contralateral side of onset. The anterior putamen was involved mildly, and there were characteristic differences in DAT reduction patterns between PD and APS patients. Conclusion 18F-FP-CIT, a DAT imaging agent, can be prepared automatically, stably and efficiently after optimization. The prepared probe provides clear imaging and reliable semi-quantitative results, which can intuitively reflect the degree and distribution of dopaminergic neuron injury in the brain, and provide an objective and accurate molecular imaging basis for the early identification and disease evaluation of PD and APS