Primary angle closure glaucoma(PACG)is the leading type of glaucoma in Asia, especially in China. PACG still has a high proportion of angle closure after laser peripheral iridectomy(LPI). Plateau iris is one of the non-pupillary blockage factors that cause angle closure. With the wide application of ultrasound biomicroscopy(UBM)in ophthalmology, the understanding of plateau iris has been deepened continually. This paper will elaborate the concept, mechanism, prevalence, relationship with angle closure, diagnostic criteria and the treatment of plateau iris, aiming to have a deeper understanding of the relationship between plateau iris and PACG, and to provide references for the treatment and research of PACG in the future.