In this study, physiological and morphological modifications of infected Vicia faba leaves by bean yellow mosaic virus (BYMV) in response to biosynthesized silver nanoparticles treatments were examined. Infected leaves showed symptoms including deformations, mottling, size reduction, crinkling and severe mosaic. Three weeks after virus inoculation, the percentage of BYMV infection, disease severity and virus concentration were significantly reduced in response to virus infection. BYMV-infected cells showed lower chloroplast number in comparison to the control. Two kinds of inclusions were detected in BYMV- infected leaves: slightly curved or straight bands sometimes looped at the end, and electron opaque crystals with varied shapes.  Spraying of biosynthesized silver nanoparticles on Vicia faba leaves helped to reduce or prevent the harmful effects produced after virus infection. Application of silver nanoparticles NPs (9-11nm) treatments after 24 hours of inoculation restored the metabolism of infected leaves to the levels of healthy controls. Silver nanoparticles treatments improved plant health by increasing the photosynthesis rates, pigment contents and levels of other parameters studied similar to control values. Moreover, silver nanoparticles treatments increased plant resistance against BYMV. This was observed through induction of chloroplast number, reduction in percentage of infected plants, decrease in disease severity and virus concentration of plants treated with silver nanoparticles treatments prior to BYMV inoculation. The present results provide an overview of the positive effects of silver nanoparticles treatments in induction of resistance against BYMV infection in faba bean leaves from physiological perspectives. To the best of our knowledge, this is the first report on the effect of biosynthesized AgNPs on physiological parameters of infected Vicia faba by Bean yellow mosaic virus.