Polyaniline decorated Silver nanoparticles (PANI@AgNPs) composites were successfully synthesized by sonochemical oxidative polymerization utilizing an equimolar amount (1:1) of AgNO3/Aniline dissolved in each 25 ml of water/methanol separately, mixed slowly, and then held in a sonicator for 45 minutes in a dark environment. No other external oxidizing agents were employed for polymerization; only AgNO3 was used as a metal precursor and as oxidizing agents. Various instrumental techniques HR-TEM, FE-SEM, XRD, TGA, UV-vis., and FT-IR were used to analyze the PANI@AgNPs. The PANI@AgNPs/GCE had good electrochemical responses and electrocatalytic activity over the detection of hydrogen peroxide (H2O2), according to a cyclic voltammogram. H2O2 is oxidized at the surface of PANI@AgNPs/GCE has clearly reveal by the voltammetry techniques of cyclic, amperometric, and differential pulse voltammetry. The detection limits 0.03 M was found at amperometric analysis for H2O2.