Abstract: Oxidative stress is assumed to be the principal molecularmechanism for the pathogenesis of organ aging and many diseases,including various tumors,neurodegenerative disorders and so on. Enhanced oxidative stress due to excess reactive oxygen species (ROS) generation leads to oxidative damage to the cellular components,such as proteins, lipids, and DNA. PET is a noninvasive, fully quantitative, and highly sensitive imaging modality that can detect ROS level in vivo. For important role of oxidative stress in diseases and aging, major ROS sensing probes have been developed,including hydroethidium(HE)and hydromethine (HM) analogue which has the ability to detect superoxide anion, and amino acids which have also been recognized as key components of cellular redox homeostasis. However, most of them are still in the preclinical studies, and the clinical transformation of oxidative stress PET imaging agents will be a major focus of future work. This review mainlyed describes the state of the art of Oxidative stress PET probes and their clinical applications in diagnosis of diseases.