In this work, silver nanoparticles (AgNPs) were synthesized by the extract of Citrus maxima (C. maxima) peel with the presence of pectin as a principal reductant and stabilizer. Parameters such as concentration of C. maxima powder, extraction temperature, and extraction time for AgNPs synthesis have been studied. The synthesized AgNPs were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), and transmission electron microscopy instrument (TEM). The synthesized AgNPs were quasi-spheres with an average particle size of 17 nm and high purity of silver phases. In addition, synthesized AgNPs exhibited good antibacterial activity against Gram-positive bacteria: Salmonella enterica (S. enterica) and Pseudomonas aeruginosa (P. aeruginosa) while no activity inhibited against Gram-negative bacteria: Staphylococcus aureus (S. aureus) and Lactobacillus fermentum (L. fermentum).