Nanotechnology is concerned with the production of nanoparticles (NPs) with restricted sizes and shapes through facile, straightforward, and medicinally active phytochemical routes. This study aims to develop an easy and justifiable method for the synthesis of Hippeastrum hybridum (HH) induced gold NPs (HH-AuNPs) and then to investigate the effects of these NPs as a free radical scavenger, an inhibitor of the two enzymes i-e Alpha-amylase (α-amylase) and acetylcholinesterase (AChE). UV-Vis spectrum at 576 nm with maximum absorbance at 1.96 confirmed the HH-AuNPs formation. Fourier transform infrared spectroscopy (FT-IR) conforms to the peaks for the functional groups of HH extract and on the surface of HH-AuNPs that are involved in the synthesis and stability of the HH-AuNPs. The average size of 10.72 nm was calculated using four major peaks 38.02°, 44.29°, 64.37°, and 77.58° of X-Rays Diffraction (XRD) analysis. The scanning electron microscope (SEM) analysis confirmed the presence of spherical shaped, monodispersed, and huge density HH-AuNPs with an average size of 30 nm. Energy dispersive X-ray (EDX) confirmed the intense sharp peak at 3.1 keV showing that Au was the main element (48.08%). The HH-AuNPs showed an excellent inhibitory efficacy against free radicals, α-amylase, and AChE as compared to HH extract and HAuCl4.3H2O salt. Our results suggest that HH-AuNPs exhibited significant antioxidant, Antidiabetic, and antialzheime activities in a concentration-dependent manner as compared to HAuCl4.3H2O and plant extract. However, further investigations are recommended to be able to minimize potential risks of application.