Due to the non-contact, simple structure, high sampling rate, high security, and high resolution, optical tomography technology has been widely used in the fields of industrial fluid monitoring and medicine and has significant research value in the academic field. Optical tomography concludes scanning stage and image reconstruction stage. In the stage of image reconstruction, the performance of the algorithm determines the performance of image reconstruction. Aiming at the problems of slow reconstruction speed and poor reconstruction quality, this paper proposes the improved Landweber reconstruction algorithm based on preset matrix. In the improved algorithm, the historical iteration information is considered, and preset matrix and acceleration term are introduced in the iteration process. In this paper, five specific distributions in the circular measurement field are used for experimental simulation, and the performance of the proposed improved algorithm is compared with that of the traditional algorithm. The results show that the performance of the proposed algorithm is significantly improved. The reconstruction error of the proposed algorithm is about 5%, which has been reduced by 48%. The quality of the reconstructed image is also significantly improved.