We report a case of incidental CuCl2 uptake at PET/CT imaging in a 61-year-old man with a biochemical recurrence of prostate cancer. Parathyroid hormone was slightly elevated (92.4 pg/mL; reference range, 18.4-80.1 pg/mL); serum calcium was in reference range (9.5 mg/dL; reference range, 8.6-10.6 mg/dL), whereas serum phosphate was slightly low (2.6 mg/dL; reference range, 2.7-4.5 mg/dL). This case highlights the ability of CuCl2, similar to radiolabeled choline, to identify the presence of hyperfunctioning parathyroid glands in patients undergoing PET/CT examination.