In accordance with the present disclosure, a hybrid electronic sheet which exhibits superior electrical property and allows biomaterial functionalization and flexible device patterning may be provided by binding a graphitic material in colloidal state to a biomaterial capable of binding thereto specifically and nondestructively. Since the electronic sheet is an electronic sheet wherein a biomaterial and an electrical material (graphitic material) are hybridized, it exhibits good compatibility with biomaterials and can be further functionalized with, for example, an enzyme that selectively reacts with a biochemical substance. Accordingly, an electrical material and a chemical or biological material may be effectively nanostructurized and it can be realized as a multi-functional, high-performance electronic sheet.