Based on the effective perspective images' segmentation and mosaicking (EPISM) printing method, the influence of the holographic element (hogel) size on the reconstructed quality is analyzed to improve the reconstructed quality of holographic stereogram. The flipping effect and diffraction effect in the spatial domain are also discussed, and the optical transfer function of the holographic stereogram is used in the spectrum domain to evaluate the reconstructed quality. Theoretical analysis and optical experimental results show that the hogel size plays an important role on the flipping effect as well as the clarity of the reconstrued 3D perspective images of the EPISM-based holographic stereogram, and the flipping effect can be improved significantly with optimized hogel size.