Objective To evaluate the usefulness of dopamine transporters (DAT) imaging in diagnosing Parkinson's disease by PET scan, and to assess the method by observing the security and its validity. Methods 18 F-FP-CIT PET was studied in 2 monkeys, 4 healthy controls, 21 parkinsonian patients with early stage and 36 parkinsonian patients with advanced stage. Results DAT uptake could be observed in bilateral caudate and putamen of monkey 1 hour after injection, the better image was seen at 3 hour.In the normal control, image shows the uptake of DAT in bilateral caudate and putamen and brain cortex at 15 min and 30 min after injection. Only caudate and putamen could be seen in the 2 hour image. In the 57 patients with Parkinson's disease, the binding uptake in contralateral caudate, anterior and posterior putamen was significantly reduced, the DAT binding uptake in contralateral posterior putamen is correlated with symptoms of PD patients. Conclusion 18 F-FP-CIT PET can evaluate the Parkinson's disease at the molecular level.DAT PET is an important clinical molecular imaging tool.