For the first time, green synthesis of silver nanoparticles was developed by treating Ag + ions with Zataria multiflora leaf extract. Leaf extract quantity, AgNO3 concentration and reaction temperature were determined as significant factors in the bioreduction reaction. Carbohydrates of the leaf extract were identified as the effective compound for reduction and capping of AgNPs. Also, TEM micrographs illustrated that micro and nano scale carbon-based materials act as structural scaffold for nucleation and growth of particles. Oxygen-bearing functional groups were identified as active groups for reduction of Ag + ions. The prepared particles were spherical from 16.3 nm to 25.4 nm with mean particles size of 20.3 nm.