Silver nanoparticles (AgNPs) are an interesting metal nanoparticle that can be incorporated into pharmaceutical products, including for diabetic foot ulcers as an antimicrobial agent. Green synthesis of AgNPs using plant extracts has been drawing much attention as it is simple, eco-friendly, stable, and cost-effective. This present study was performed to evaluate the potential of three Indonesian medicinal plant extracts, namely Phyllanthus niruri (PN), Orthosiphon stamineus (OS), and Curcuma longa (CL), as reducing and capping agents in the green synthesis of AgNPs, and to optimize their concentrations. Based on the yields and characteristics of the formed nanoparticles, which were analyzed using a UV-Vis spectrophotometer, particle size analyzer, scanning electron microscope, and X-ray diffractometer, Phyllanthus niruri extract at a concentration of 0.5% was concluded as the best extract in the green synthesis of AgNPs. It is thereby a prospective reducing and capping agent for further scale-up studies.