A probe of a scanning probe microscope having a sharp tip and an increased electric characteristic by fabricating a planar type of field effect transistor and manufacturing a conductive carbon nanotube on the planar type field effect transistor. To achieve this, the present invention provides a method for fabricating a probe having a field effect transistor channel structure including fabricating a field effect transistor, making preparations for growing a carbon nanotube at a top portion of a gate electrode of the field effect transistor, and generating the carbon nanotube at the top portion of the gate electrode of the field effect transistor.