Silver nanoparticles were synthesized at 293÷ 353 K temperature range by NaBH 4 and HCOOH solutions with low concentration at polyethyleneglycol having average molecular weight of 40000 and 200 kDa gum arabic medium. Obtained silver nanoparticles were studied using methods of X-ray diffraction, UV-Vis, FTIR spectroscopy, scanning electron microscope. It was determined that sizes of silver nanoparticles which stabilize at polymer medium vary from 12 to 26 nm range depending on mole ratio, temperature and reduction medium of initial substances. It was shown by FTIR-spectroscopy that-OH and-COOH groups in polymer take an active part in stabilization of silver nanoparticles. It was determinated by UV-Vis study of silver nanoparticles containing polymer composition in aqueous condition that 412 nm which is specific to silver atoms do not change sharply for 4-5 days.