This work is an evaluation of the plant diversity of the white Wormwood formations (Artemisia herba-alba Asso.) in the steppes rangelands of the south-eastern zone of Saï (municipality of Maamora, Western Algeria). For this purpose, twenty-one phytoecological statements are carried out on three sample stations: an exclosure station where the white Wormwood is well developed and two other stations not protected where in one, the white Wormwood is moderately degraded and in the other one, it is strongly degraded. The factorial correspondences analysis (FCA) and the ascending hierarchical clustering (AHC) carried out on the floristic and edaphic parameters measured on these stations led to a hierarchy of the ecological factors determining the diversity of the studied plant formations with white Wormwood. The vegetation studied is marked by the dominance of the therophytes, particularly in the third station (very degraded station), while the exclosure station is essentially characterized by a high recovery rate and an important phytomass.