Reactive oxygen species are kinds of highly reactive substances, including superoxide radicals, hydrogen peroxide, singlet oxygen, and hydroxyl radicals. Oxygen molecules, as oxidants, are more stable and need to be converted to highly reactive species before they can further react with other substances. In chemical reactions, especially catalytic oxidation reactions, the type of reactive oxygen species, its formation, and its diffusion behavior determine the direction and rate of the reaction. In the field of life sciences, reactive oxygen is involved in energy conversion, oxygen balance and other important physiological processes, which are closely related to aging and disease. However, due to its short half-life and strong reactivity, qualitative and quantitative testing of reactive oxygen species is difficult. Choosing suitable detection methods and improving the temporal and spatial accuracy of the detection is important for environmental chemistry and life science research. This work introduces and compares the basic principles, research advances, and applications of reactive oxygen detection methods in environmental and life fields, and compares the advantages, disadvantages, and applicability of various methods. The theoretical calculation and detection of oxygen species in heterogeneous catalysis are also introduced, and the future research direction of reactive oxygen species in catalytic oxidation and other fields is discussed.