Abstract: Objective and Methods Good reservoir injectivity is an essential requirement for a high-quality CO₂ geological storage (CGS) site. Salt precipitation near injection wells caused by brine evaporation and crystallization is one of the key factors leading to reservoir injectivity impairment. To determine the differences in salt precipitation and reservoir damage in different reservoirs, this study selected sandstone samples with different pore structures, and carried out salt precipitation simulation experiments based on high-temperature and -pressure fluid displacement system. Using thin section, scanning electron microscopy and energy spectrum, micro-area X-ray fluorescence spectroscopy, high-pressure mercury intrusion, nuclear magnetic resonance, and relative permeability, this study aimed to determine the effects of the initial reservoir pore structure on crystal characteristics and distribution patterns of salt precipitation. Results and Conclusions High-porosity and -permeability reservoir with good pore structure is characterized by a low number of salt precipitates, small size of salt crystals and dispersed single crystals, with the maximum salt precipitation content of approximately 0.2%. With the deterioration of the pore-throat size, sorting and connectivity, the number and size of salt crystals and aggregates increase, with the maximum salt precipitation content reaching approximately 4.7%. With the change of the reservoir pore structure from the homogeneous large pore-throat type to the heterogeneous small pore-throat type, the distribution patterns of salt precipitation vary from weak homogeneous salt precipitation dominated by in-situ brine evaporation to intensive local salt precipitation dominated by brine capillary backflow to intensive homogeneous salt precipitation controlled by brine capillary backflow and salt solute diffusion. Increasing salt precipitation results in increasing damage to the reservoir structure and the injectivity in the vicinity of injection wells. The porosity-permeability damage rate increases from 1% in large pore-throat reservoirs to 26% and 38% in small pore-throat reservoirs. Reservoirs with different initial pore structures have different characteristics of salt precipitation and thus varied risks of injectivity impairment. This could provide a theoretical basis for mitigating reservoir damage during CO₂ geological storage in saline aquifers and facilitating the efficient deployment of CO₂ geological storage.