Uniformly sized and shaped gold nanoparticles (AuNP) were produced by microwave irradiation using Euphorbia tirucalli latex. The AuNPs were characterized by ultraviolet visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering, zeta potential, and transmission electron microscopy (TEM). UV–Vis analysis was employed to detect the characteristic surface plasmon resonance pattern of the AuNPs (550?nm). The carboxylic and polyphenolic groups were associated with the euphol-capped AuNP, which was confirmed using FTIR spectroscopy. The AuNPs studied here show a z-average diameter varying from 35 to 500?±?0.8?nm. TEM reveals that the particles were spherical and polydispersed. The latex itself is very toxic and can be harmful during manipulation, thus highlighting a negative aspect in it use. However, we have demonstrated that the isolation procedure did not impair the reduction action of the dry latex powder. This study provides a robust solution for the synthesis of stable capped gold nanoparticles. Furthermore, the dried powdered E. tirucalli latex seems to be an attractive capping agent for nanoparticles in drug delivery.