As an important part of the optical system, high refractive index optical glass has excellent comprehensive performance such as high refractive index, high transmittance and high chemical stability, and can expand the field of view angle (FOV) of devices such as digital cameras, microscopes and virtual reality (VR glasses). At present, the research of high refractive index optical glass mainly involves, 1) the preparation of high refractive index glass without traditional glass forming oxide, which cannot be prepared in large size. 2) By adding heavy metal oxide to lanthanide glass high refractive index, enhanced internal transmittance, and improved glass-forming ability are achieved, and this has now been successfully realized through engineering-scale production. This paper summarizes the research progress of high refractive index optical glass, and discusses the development trend and application.