F-NaF is a radiopharmaceutical widely used in PET imaging to detect bone metastases. Several cases of F-NaF uptake from brain metastases have been described, but a specific protocol for the evaluation of brain metastases with F-NaF has not been developed yet. Here we report images of F-NaF PET/CT, standard CT, and MRI of a brain metastasis in a patient with non-small lung cancer. Through a dynamic acquisition procedure, we have identified the first minutes after injection as the preferable time point of imaging acquisition for the study of brain metastases with F-NaF.