Abstract: Glioma is the most common intracranial tumor, accounting for 40%–55% of brain tumor cases. The time of diagnosis affects the prognosis of patients. The application of PET imaging agents, which is a noninvasive method of diagnosis, to glioma has increased rapidly in recent years. ¹⁸F fluorothymidine (¹⁸F-FLT) is a common PET imaging agent, which is a radioactive thymidine analog and is used to evaluate cell proliferation. This imaging agent can provide more information than that from other imaging examinations and agents during and after the treatment of glioma. In this review, we mainly discuss the present research status of glioma imaging agents in the brain, including the ¹⁸F-FLT imaging mechanism; the diagnosis, classification, and identification of recurrence and necrosis; the curative effect evaluation and prognosis of glioma from ¹⁸F-FLT; and the relationship between ¹⁸F-FLT and Ki-67.