The green synthesis of Cymodocea serrulata silver nanoparticles was rendered by using seagrass leaves extract. These extracts acted as a capping and reducing agent in stabilizing the formation of AgNPs. The obtained NPs were characterized by using UV, FTIR, SEM, TEM, EDX and XRD methods. UV–V is spectra of the reaction mixture of silver nitrate solution with extract the peak was observed at 422.30nm indicating the presence of silver nanoparticles. SEM analysis was carried out to understand the topology and the size of the NPs, which showed the synthesis of higher density polydispersed spherical NPs of various sizes that ranged from 22 to 65nm and crystalline nature of the nanoparticles. TEM analysis illustrated the particles are spherical in shape and appear well-dispersed with a size range from 18-65 nm. The EDX elemental analysis of the synthesized silver nanoparticles showed highest proportion by weight of silver (80.22%) followed by Chloride (16.45%) and Oxygen (4.43%). The crystalline nature of AgNPs was further established from X-ray diffraction (XRD) analysis display the XRD pattern of nanoparticles acquired from colloid samples. The antioxidant property of green synthesized AgNPs from Cymodocea serrulata extract was determined to be nearest to the IC50 values of standards. This shows the ability of green synthesized AgNPs to scavenge free radicals. The green synthesized AgNPs of Cymodocea serrulate can be further exploited as a potential candidate for antioxidant agents.