Green synthesized metallic nanoparticles are continually receiving attention as antimicrobial agents and catalyst for degradation of a host of organic compounds. In this study, silver nanoparticles were synthesized using Aspilia pluriseta extracts and evaluated for their antimicrobial and photocatalytic activity. Using a UV–Vis spectrophotometer, the surface plasmon resonance observed at 427 nm indicated the materialization of silver nanoparticles. Probable vibrational stretches that are characteristic of silver nanoparticles such as –OH stretching vibrations and –CH2 vibrational stretch, were identified using an FT-IR spectrophotometer. In order to understand the morphology and composition of the synthesized nanoparticles, they were studied further using scanning electron microscope (SEM), dynamic light scattering analyzer (DLS), transmission electron microscope (TEM) and X-ray diffractometer (XRD) hence revealing formation of crystalline, spherically shaped silver nanoparticles. The synthesized silver nanoparticles (AgNPs), exhibited broad-spectrum activity which was concentration dependent against; two-gram positive bacteria (Bacillus subtilis and Staphylococcus aureus), two-gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and the fungal (Candida albicans). Effectiveness of the nanomaterials in photocatalytic degradation was based on irradiation time. Decolorization and degradation of the dye took less than 30 min. [ABSTRACT FROM AUTHOR]