Due to their unique electrical, geometrical, mechanical and biocompatible properties, single-walled carbon nanotubes (SWNTs) are attractive materials for the construction of nanoscale field-effect transistor (FET) biosensors. At present, biosensors based on CNTFET are required in various applications, including clinical diagnostics, environmental testing, food analysis, and bioterrorism detection technologies. In this paper, we report the fabrication of carbon nanotube field-effect transistors (CNTFETs), by applying AC Dielectrophoresis (ACDEP) method to deposit and align SWNTs across the source and drain of CNTFETs to form the conductive channel. By controlling the experimental condition, we can connect the electrodes with many bundles of SWNTs, and with the transfer characteristics, we known the fabricated FET has good performance in electronic properties.