The World Health Organization (WHO) has classified Candida albicans as one of the most dangerous pathogenic fungi in the world because of its ongoing development of resistance to anticandidal medicines that are now on the market. The present study addressed this issue by offering a straightforward, one-step, economical, and secure method for the manufacture of novel functionalized anticandidal selenium nanoparticles (Se NPs) against C. albicans ATCC10231 using methanolic fruit extract from Washingtonia robusta H. Wendl. Gas chromatography-mass spectrometry (GC-MS) was used to analyze the bioactive chemicals in the W. robusta H. Wendl extract. Heptasiloxane (44.43%), oleic acid (13.07%), and undecanoic acid,11-bromo-, methyl ester (4.02%) were among the seven biochemical ingredients found in this methanolic fruit extract. The resulting nanoparticles were characterized using various techniques, including ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), zeta potential analysis, and transmission electron microscopy (TEM). The anticandidal efficacy of the Se NPs was evaluated against Candida albicans ATCC10231 using agar well diffusion method, and minimum inhibitory concentration (MIC), and minimum fungicidal concentration (MFC) were determined. Results indicated that the Se NPs exhibited a good anticandidal activity with an inhibition zone 32 ± 0.04 mm, MIC 15 µg/ml, and MFC 15 µg/ml against C. albicans. These results indicated to the promising anticandidal action of the green synthesized Se NPs which might be applied in different medicinal and pharmaceutical fields.