In this research some aspects of electron transfer (ET) in electrochemical system based on immobilized gold nanoparticles (AuNPs) and glucose oxidase (GOx) were investigated. It was shown that in the design of AuNPs and GOx modified graphite rod (GOx/AuNPs/GR) electrode the AuNPs are facilitating the electron transfer from GOx toward graphite rod electrode. It was determined that significant electrode currents and well-defined oxidation/reduction peaks were registered at potential sweep rate of 0.1 V s(-1). Anodic peaks in cyclic voltammograms, which were observed in the presence or absence of glucose (Glu), were proportional to the square root of the potential sweep rate (v(1/2)) in the range of 0.05-0.3 (V s(-1))(1/2), which is indicating that the electrochemical reaction is diffusion controlled. (C) 2017 The Electrochemical Society. All rights reserved.