The high porosity characteristic of porous concrete makes its cementitious materials susceptible to strength degradation due to external chemical corrosion. Currently, research on its resistance to chemical corrosion is relatively limited, primarily employing silicate cement as the main binder. Therefore, this study investigates the impact of different sodium silicate moduli on the chemical corrosion resistance of alkali-activated porous concrete. The experiment evaluates its performance under conditions of sulfate ion corrosion, accelerated carbonation, and coupled corrosion. The results indicate that the developed porous concrete maintains sufficient strength and porosity after chemical corrosion, meeting the minimum standards of relevant industry standards (JIS A, 17 MPa). Lower alkali activator moduli enhance corrosion resistance, likely attributed to increased hydration and a denser microstructure. This research provides necessary groundwork and theoretical support for the practical application of alkali-activated porous concrete in warm coastal regions.