Herein, we demonstrated an immobilization strategy for high biological activities and high performed biosensors without conformational changes by using bioconjugates consisted of fusion proteins and reduced graphene oxide-gold nanoparticle hybrid materials (RGO-Au). The GBP-OPH/RGO-Au nanobio-conjugates were expected that hybrid systems enable to improve enzyme stability, and biocatalytic activity, and electron transfer over the enzymatic reaction, which attributed to favorable morphology of immobilized GBP-OPH. The particle size and distribution of Au on RGO were characterized by TEM and AFM images. The electrochemical properties of GBP-OHP/Au-RGO hybrids were analyzed by cyclic voltametry and impedance analysis. The amperometric measurements were performed for detection of OP compounds by flow injection method.