Silver Nanoparticles (AgNPs) recently have received considerable attention due to their unique chemical and physical properties which affect their sizes and shapes. The need to optimize the synthesis of Silver nanoparticles (AgNPs) is essential to develop effective colorimetry censors. Herein, the effect of sodium chloride on the reduction process of silver nitrate (AgNO3) into the final product of AgNps had been investigated. AgNPs have been synthesized using sodium chloride and polyvinyl alcohol (MW: 60,000 Da) as a reducing agent and a capping agent, respectively. The particles were collected and examined using ultraviolet-spectroscopy, transmission electron microscopy, and X-ray diffraction. The result showed that the concentration of sodium chloride affects the reduction process of Ag+ into AgNPs. At 1% concentration of sodium chloride, AgNPs were formed in 7 hours. In contrast, by reducing the concentration of sodium chloride to 0% has resulted slower AgNPs formation in 24 hours. The high sodium chloride concentration leads to the formation of silver chloride, which been investigated using the X-ray diffraction analysis. Besides, the transmission electron microscopy analysis showed that two different-shaped AgNPs were formed from the reaction. Therefore, the formation of AgNP particles was increased through the formation of transition molecule, silver chloride, by adding a higher concentration of sodium chloride.