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Carbonation curing of cement-based materials has recently received increasing attention as a CO 2 utilization technology. This study aimed at investigating the effects of carbonation curing on the performance of ordinary Portland cement (OPC) pastes with dolomite additive (DPC). The CO 2 uptake capacity, after being normalized to carbonation active components, significantly increased with larger dolomite mixing ratios. For DPC-25% samples under 2.5 MPa curing pressure, the maximum CO 2 uptake capacity reached 23.6 wt%, which was 23% higher than that of pure OPC samples under the same condition. Effects of water to solids (w/s) ratio and temperature on carbonation are two-sided. The optimum w/s ratio for CO 2 uptake capacity of DPC-15% samples was approximately 0.20, while the optimum temperature was equal to 60 • C or higher than 60 • C. The CO 2 uptake capacity increased with finer particle size and higher CO 2 curing pressures. Compared to large particles, smaller particles are more likely to have a better dilution effect, providing more contact surface for carbonated precipitation. From the pore structure changes perspective, carbonation products filled the interface between the dolomite and amorphous particles. DPC-25% samples with higher dolomite mixing ratios provided more pores and pathways for gas diffusion, and exhibited a more uniform structure, thereby contributing to the highest compressive strength values of DPC-25% samples (63.8 MPa) among all the DPC samples. These findings imply the possible feasibility of dolomite as an additive in carbonation cured building materials.