In the present study a simple and eco-friendly synthesis of AuNPs using stem extract of C.reflexa has been carried out. The colour changed from light yellow to purple colour which indicates the synthesis of AuNPs. The synthesised NPs showed SPR at 562 nm. SEM and TEM analysis confirmed that the particles were spherical in shape and mean particle size was 48nm. Hydrodynamic radius of NPs was estimated to be 76 nm with -31.6 mV zeta potential when the colloidal solution was analysed by DLS. FTIR spectroscopy confirmed various biomolecules such as proteins, flavonoids, and phenolics were responsible for capping and stabilizing the AuNPs. Antibacterial activity of AuNPs investigated using disc diffusion method revealed significant inhibitory activity against E.coli and S.aureus. The nanoparticles also showed potential anticancer activity against HeLa (human cervical) cell line. It is an interesting study showing the stem extract of C.reflexa acting as an efficient reducing agent in the formation of AuNPs with significant activity against human pathogenic bacteria and cytotoxic effect on HeLa cell line