[en] Objective: To prepare and label the ¹²⁵I-β-CIT and study its biological distribution in animal. Methods: ¹²⁵I-β-CIT was prepared by the peracetic acid method and the chloramine-T method, and dopamine transporter (DAT) binding properties of ¹²⁵I-β-CIT were examined by in vivo biodistribution and inhibition studies in mice and whole body autoradiography in rats. Results: The radiolabelling yields of the peracetic acid and the chloramine-T methods were (53.4 +- 7.9)% and (88.4 +- 3.49)%, respectively. Following intravenous injection in mice, ¹²⁵I-β-CIT showed high accumulation in striatum, time to peak level uptake was 2 h after injection. GBR12909 significantly inhibited ¹²⁵I-β-CIT binding in striatum, while clomipramine significantly inhibited ¹²⁵I-β-CIT binding in hippocampus and cerebral cortex. The rat whole body autoradiography showed that the clearance of the tracer occurred through the hepatobiliary route. Conclusions: The results indicate β-CIT is an agent suitable for DAT imaging and can be used for the study of Parkinson's disease