Nanotechnology has been widely growing in many industries with its application in science and technology because of its excellent physical and chemical properties. The product of nanotechnology is called as nanoparticles. Green synthesis is proved to produce non toxic nanoparticles. Green synthesis using plant extract provides a great reduction and stabilization of metal ions by combination of biomolecules and phytochemicals, which are highly contained in the plant extract. Cilantro (Coriandrum sativum) is known as a plant that is rich in polyphenols and phytocemicals, like carotenoids and phenolic groups (phenolic acids, flavonoids, tannins, stilbenes, and lignans) that may be worked in green synthesis of silver nanoparticles (AgNPs). The aim of this research was to study green synthesis of AgNPs using leaves and stems extracts of cilantro. Dried leaves and stems extract of cilantro were extracted using different ratio of water to ethanol as the solvent (1:0, 1:1, and 0:1). All of the extracts were used for the synthesis of AgNPs, and then further analyzed for the yield and antioxidant activity. AgNPs synthesized from cilantro’s leaves extracted using 1:0 water to ethanol ratio had the highest yield of AgNPs (13.98±0.06 %) and lowest IC50 value (63.82±2.65 mg AgNPs) resulted with size approximately 102.1 nm. AgNPs were treated with calcination process since it has the potency to increase the antioxidant activity. However, AgNPs which was calcinated at 100oC, 300oC, and 500oC had significantly lower antioxidant activity (higher IC50 value) as in comparison to non-calcinated AgNPs.