▎ 摘　　要

Construction of graphene-based nanocomposite system is an effective approach for the expansion and enhancement of applications of graphene. Owing to the synergy effect of different constituents, the electrical, chemical and electrochemical properties of graphene can be greatly improved, leading to the expansion and enhancement of the electrochemical effects of graphene. Graphene nanocomposites provide a novel and efficient electrochemical platform for the immobilization of oxidoreductase and the realization of direct electrochemistry, which can apply in the design and preparation of third-generation electrochemical biosensors, showing excellent sensitivity and selectivity towards the detection of glucose, cholesterol, Hb, DNA, H2O2, O-2 and small biomolecules. This paper reviews the progress of graphene nanocomposites applying in electrochemical biosensors, including the nanocomposites of graphene with precious metal, metal oxide/semiconductor nanoparticle, polymer, dye molecule, ionic liquid and biomolecule. The future development and application prospect of graphene in electrochemical fields are also discussed.