The development of nanostructured functional materials with unique properties is of great interest in the current research of materials science and chemical engineering, and advances the improvement of many applications, especially chemosensors and biosensors aiming at rapid and cost-effective detections of various targets with enhanced sensitivity and selectivity. Therefore, this dissertation focuses on the fabrication of novel nanostructured materials, including noble metal functionalized nanofibers and metal oxide-based nanostructures, and further discusses their enhanced performances in sensing applications. Specifically, noble metals have been deposited on the surface of electrospun nanofibrous template via an appropriate physical or chemical approach, including sputter coating, electroless plating, and electrodeposition. The resultant composite nanomaterials, inheriting not only the excellent conductivity and superior catalytic ability of the noble metals, but also the large surface area and high porosity of the electrospun nanofibers, have been successfully applied in both vapor/gas phase detection and liquid phase detection for various analytes with dramatically improved sensing performances. On the other hand, as promising substitutes for noble metals in the context of sensing application, metal oxides with different nanostructures are facilely synthesized via direct thermal oxidation, galvanic replacement reaction, or hydrothermal reaction. The excellent electrocatalytic properties of the as-prepared nanostructured metal oxides are investigated in the detection of hydrogen peroxide as a model compound. The methodology for the fabrication of novel nanomaterials developed in this dissertation can be potentially extended to the synthesis of other novel multifunctional nanomaterials for a wider range of practice areas beyond (bio)sensing.