Effect of carbonation curing on the early resistance to carbonic acid solution corrosion of cement-based materials was investigated. The compressive strength, and corrosion depth of carbonation cured specimens were tested after immersion in carbonic acid water for varying periods. The microstructure and corrosion mechanisms were analyzed by X-ray diffraction, thermogravimetric analysis, low-field nuclear magnetic resonance, and scanning electron microscopy. The results show that carbonation curing improves the initial compressive strength via forming calcite to fill pores, making the structure more compact and hindering inward diffusion rate of carbonic acid solution. A dense, slower-dissolving calcite layer around C-S-H gel reduces calcium-corrosion, decreasing both the corrosion depth of mortar specimens by 51%-68% after 90-d immersion and losing the strength after carbonic acid water corrosion. The early-stage corrosion was dominated due to C3S, C2S, and CH corrosion, accompanied by CaCO3 decalcification. The middle- and later-stage corrosion involves the decalcification of CaCO3 and C-S-H gel.