For the first time in this study, gold nanoparticles (AuNPs) were biosynthesized by the eco-friendly and cost-effective procedure using Presley leaf (Petroselinum crispum) extract then used as antioxidant, anticancer, antibacterial and photocatalytic agents. Different four-volume of the extract 2.5 mL, 5 mL, 10 mL, and 20 ML named AuNPs(A), AuNPs(B), AuNPs(C) and AuNPs(D) were used to module the size and shape of AuNPs. The prepared NPs were characterized by various techniques including UV-Vis absorption spectroscopy, Transmission Electron Microscopy (TEM), dynamic light scattering (EDX), and X-ray diffractometric (XRD). TEM imaging confirmed the formation of spherical, semi-rod aggregates, and flower-shaped NPs. The reduction and stabilization effect of the plant extract to fabricate AuNPs were explained by FTIR analysis. The four AuNPs provided high antioxidant ability, while AuNPs(D) was the best one. The NPs showed an emerging antimicrobial activity against two gram-negative microbes and not effective against the gram-positive microbes. The photocatalytic capacity for degradation of methylene blue dye was achieved after only one minute (the four samples have an equal effect). The AuNPs(D) provide the best anticancer activity on the human cancerous colorectal cell line using MTT assay rather than the other three AuNPs. The results spotlight for using Presley as a common cheap plant for bio-fabricating AuNPs who possess huge multifunctional applications. (C) 2020 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.