Abstract: The electrochemical detection of hydrogen peroxide was realized by electrodeposition of functionalized gold nanoparticles modified electrode. By studying the electrochemical behavior of self-assembled electrode in hydrogen peroxide,the better conditions for the detection of hydrogen peroxide were obtained and the standard curve for the detection of hydrogen peroxide was established. The optimized conditions were as follows:Cysteine/Mercapto ethylamine,particle size of gold nanoparticle 15 nm,concentration 0.05 mol/L,scanning speed 110 mV/s,pH6.0 when detecting hydrogen peroxide,etc.. The correlation coefficient r was 0.997,the detection limit was 0.129 μmol/L,and the quantitative limit was 0.431 μmol/L,with good reproducibility and stability,high precision,and strong anti-interference ability to glucose,glycine,ascorbic acid,potassium salt,sodium salt,etc.. The modified electrode had good performance in the detection of hydrogen peroxide. In the actual sample detection,the recovery was 92.1%~95.6%,RSD was 2.26%~4.52%,which could be used for the determination of hydrogen peroxide in the actual sample.