The present invention relates to an AFM (atomic force microscope) cantilever including a field effect transistor (FET) and a method for manufacturing the same; and, more particularly, to a method for manufacturing an AFM cantilever including an FET formed by a photolithography process, wherein an effective channel length of the FET is a nano-scale. Therefore, The present invention can easily implement a simulation for manufacturing the AFM cantilever including the FET by accurately controlling the effective channel length. And also, the present invention can manufacture the AFM cantilever including the FET having the effective channel ranging several tens to several hundreds nanometers by applying the low price photolithography device, thereby enhancing an accuracy and yield of the manufacturing process and drastically reducing process costs.