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Purpose: The application of limited-angle computed tomography(CT)has great expectation in some clinical circumstance such as dental CT imaging.Existing iterative reconstruction algorithms could not reconstruct high-quality images using finite iterations.One reason is selection of initial image would influence the iterative reconstruction performance.In this work,we proposed to produce optimized initial image followed by total variation(TV)based iterative reconstruction by the feature of image symmetry.Methods: Based on what we found that the outer contours in some of CT images are roughly axis-symmetrical,the proposed method contains four steps: 1)reconstruct image by FBP; 2)calculate and locate the symmetry axis of the object in the image; 3)fill the region containing severe artifacts with artifact-free region in the image according to symmetry axis; 4)the processed image in step 3 is used as initial image for projection on convex sets with total variation(POCS-TV)iterative algorithm to reconstruct CT images.The proposed method uses the image symmetry to eliminate the deformation artifacts and supply POCS-TV with a good initial image.Digital Shepp-Logan and real head phantoms are used to verify the feasibility of the proposed method.Results: For simulation experiments,compared with zero image and FBP image as initial images for POCS-TV,image by our method as initial image for POCS-TV can reconstruct better results with 92%(0.0002<0.0024)gains in terms of the mean-square errors(MSE)measure and with 46%(22.99dB>12.42dB)gains in terms of signal-to-noise ratio(SNR)measure.Reconstruction of the real head phantom also validates the superiority of the proposed method.Conclusions: The experimental results indicate that the proposed method effectively removes the artifacts and significantly accelerates the iterative convergence rate.