Based on the theory of acousto-optic tunable filter (AOTF), the design method of the imaging spectrometer is presented and the prototype of the imaging spectrometer is produced with the band from 0.45 μm to 0.95 μm. The prototype is consisted of three parts, which are the fore-telescope system with 6×, AOTF components and the imaging lens with the focus of 70 mm. The focus of the prototype system is 420 mm, which collects +1 diffraction order. The target imaging experiments are performed to provide the image and spectrum information of target sampling points such as the sky, near and far buildings, trees and windows, in which the near building and the far building have the same spectrum characteristics. Experimental results show that the prototype can provide not only the space information of the target such as size, shape and relative position, but also obtains the spectrum characteristics of a pixel of the image. The same target has the same spectrum information which is not related to the detection distance. So the kind of the targets can be recognized according to different spectrum information, which has practice value to target recognition.