This study investigated the ecological characteristics, vegetation structure and phytochemical profile of Echinops spinosissimus L. across two contrasting Egyptian habitats: The Deltaic Mediterranean Coast and the Isthmic Desert. Vegetation analysis revealed a predominance of ephemeral species adapted to fluctuating moisture conditions. Soil characteristics differed markedly between habitats, with the coastal site exhibiting loamy sand texture and higher water-holding capacity, while the desert habitat reflected more stressful environmental conditions. Phytochemical analysis identified 17 amino acids across both populations. The Isthmic Desert ecotype showed significantly higher levels of phenols, ascorbic acid, tannins and alkaloids, accompanied by enhanced antioxidant activity (DPPH assay). In contrast, flavonoids and anthocyanins were more abundant in the Deltaic Coast ecotype. These variations highlight the critical role of environmental stressors, particularly water availability and salinity, in modulating secondary metabolite accumulation. The findings underscore the adaptive metabolic plasticity of E. spinosissimus and it’s potential as a source of bioactive compounds under stress conditions.