The present invention discloses a computed tomography (CT) image reconstruction method using two-dimensional images at different angles as well as a two-dimensional virtual matrix on a basis of spherical space, to process projection, comparison, and correction. Thus, it can obtain the tomography within predetermined difference value to reduce computational and storage space. Matching the parameters of energy source and image capturing can further shorten energy radiation on an object's (i.e. a human body) exposure time, in order to reduce radiation effects of energy sources (i.e. as X-rays) of the object (i.e. as a human body).