Ecologo-phytocenotic features of the cenopopulations of the rare, endemic species Iris alberti Regel in the Zailiysky Alatau (Northern Tien Shan, Kazakhstan) are considered in the monograph. Plant communities with the participation of Iris alberti and their floristic composition represented by 227 species are described. Of these, seven more: Tulipa ostrowskiana, Paeonia intermedia, Rheum wittrocki, Armeniaca vulgaris, Malus sieversii, Atraphaxis muschketowii and Euphorbia yaroslavii are included in the Red Data Book of Kazakhstan. In addition, data on the number and structure of its cenopopulations, seed productivity and anatomo-morphological characteristics of vegetative and generative organs are given