Parathyroid cancer is an uncommon type of malignancy, which is frequently associated with poor prognosis. Clinical manifestations are caused by elevated serum calcium and parathyroid hormone (PTH). Diagnostic imaging studies as neck ultrasonography, technetium Tc 99mTc-sestamibi whole body scintigraphy, CT, and MR are already established tools for this malignancy. Nevertheless, the role of 18F-FDG PET/CT remains unknown in this scenario, with few published studies in literature. Hence, in this article, we aimed to report an illustrative case of increased skeletal FDG uptake associated with high calcium and PTH levels.