In recent years, optical imaging and detection technology has been increasingly used in the field of biomedicine, which has many excellent characteristics such as high detection sensitivity, good biological safety and non-invasiveness. The development of this technology benefits from the optical properties of fluorescent substances (such as dyes, fluorescent proteins) and the development of optical imaging devices. Compared with traditional downconversion optical imaging methods, upconversion optical imaging has anti-Stokes shift luminescence properties. The optical imaging method shows good application prospects in the field of biomedicine, and the imaging method can avoid some disadvantages of downconversion luminescence. For example, the use of near-infrared light excitation can increase the penetration depth of light into the tissue, avoid the autofluorescence of the organism, and cause less damage to the tissue. Because of the particularity of this imaging method, it is necessary to introduce and review its applications in the field of biomedicine, including imaging detection and disease treatment. This has guiding significance for the rational use of upconversion luminescence technology and the rational design of upconversion luminescence materials.