In order to overcome some disadvantages of the conventional computer tomography,such as multiple projection directions,complicated systems,the tomography reconstruction based on three projection directions is proposed.Algebraic Reconstruction Algorithm suitable for fewer views is selected and its revised method which can well improve reconstruction precision and restrain salt-pepper noise is applied.The iteration numbers impacting on image quality and velocity and the impact that different shapes of original images on the reconstruction image quality are analyzed and discussed.The simulation results are presented,which show that the stable reconstruction can be gotten after 300 iteration numbers,tomography reconstruction based on three projections can be well realized for the axis-symmetric objects.The analysis results can provide some theory instruction for the further work on digital holographic tomography based on three projections.