Silver nanoparticles (Ag NPs) were prepared using Cassia auriculata leaves extract as a reducing agent via green synthesis method. From the PXRD, UV-Visible, FTIR, studies the synthesized NPs were characterized. The morphologies of the prepared NPs were studied by SEM and TEM analysis. The synthesized NPs were tested for antibacterial and anticancer studies. The PXRD data indicated that the synthesized nanoparticles belong to cubic phase structure. Presence of strong silver peaks was confirmed by EDAX studies. The SEM and TEM data revealed that spherical like structure were obtained. Antibacterial (MIC from 75 to 150 μl) activities were noticed for green synthesized Ag NPs. Furthermore, in vitro studies revealed dose-dependent cytotoxic effects of Ag NPs treated PC-3 cell line. This is the first report on the green synthesis of Ag NPs using leaves extract of C. auriculata. Results of present study could contribute to synthesize new and cost-effective drugs from C. auriculata by using green approach. Copyright © VBRI Press.