The useful reconstruction technologies for neutron penumbral imaging are all linear method, and computed tomography (CT) is one of linear methods. The principle of the CT reconstruction for neutron penumbral imaging is introduced, and the detecting image with penumbral imaging, which is extracted and differentiated along radial direction, can be reconstructed by the CT method. The detecting imaging with different noises is decoded by convoluted backprojection method, and the advantages and disadvantages of the CT reconstruction are analyzed. According to the results, the source distribution can be reconstructed by the CT method, and the higher the signal-to-noise ratio of the detecting imaging is, the better reconstruction result is. The point spread function doesn′t needs to be fully simulated before decoding, and the results will not be interfered by the useless data, because the useful data can be automatically picked from the penumbral region, and the useless data will be deleted in the bright and dark regions.