The performance of integral imaging three-dimensional (3D) display is limited by the limited depth-of-field. A method for enhancing the depth-of-field of integral imaging is proposed. This method adds an aperture stop array in the conventional integral imaging system, and the aperture stop array is used to limit the divergence angle of each pixel in the display panel. The principle of integral imaging is analyzed and the relationship between the size of aperture stop and the depth-of-field is studied in detail. Both the proposed method and conventional method are simulated by optical design software ASAP, and the simulation results show that the depth-of-field of the proposed method is 1.5 times of the conventional method when the aperture stop diameter accounts for 64% of the pitch micro-less. The experimental results verify the correctness of the theoretical analysis.