In this study, photocatalytic CdS nanoparticles were synthesized via a chemical precipitation method using Elaeagnus angustifolia (oleaster) fruit extract as a green bio- assisted agent. The use of plant-derived extract provided an environmentally friendly synthesis route, where naturally occurring phytochemicals acted as reducing and stabilizing agents, influencing the size and surface characteristics of the nanoparticles. The synthesized CdS nanoparticles exhibited strong absorption in the visible light region, indicating their suitability for photocatalytic applications. The photocatalytic performance of the obtained nanomaterials suggests their potential effectiveness in the degradation of organic pollutants present in air and water environments. Moreover, the integration of nanomaterial synthesis with the ecological utilization of oleaster, a salt- and drought-tolerant plant widely used in soil restoration, highlights a sustainable approach combining environmental remediation and green nanotechnology. This work demonstrates the potential of bio-assisted CdS nanomaterials for advanced environmental purification applications.