[Objective] Owing to its abundant availability, aeolian sand can be used in concrete production. To investigate the influence of curing age on the pore structure of aeolian sand concrete, concrete specimens are prepared by replacing river sand with varying amounts of aeolian sand, and the effects of aeolian sand content and curing age on the development of pore structure and compressive strength are explored. [Methods] In the experiments, compressive strength was used as a macroscopic indicator for aeolian sand concrete specimens with different aeolian sand contents at different curing ages. At the microscopic level, nuclear magnetic resonance (NMR) was employed to analyze the internal pore structure, including T₂ spectrum, porosity, free fluid saturation (MFFI), and bound fluid saturation (BVI). Scanning electron microscopy (SEM) was used to observe the internal microstructure and monitor structural changes in the concrete. [Results] Results showed that the internal porosity of concrete gradually decreased with increasing curing age, while the compressive strength increased correspondingly. At the same curing age, the compressive strength of concrete initially increased and then decreased as aeolian sand content increased. The optimal improvement occurred at 25% aeolian sand replacement. At 28 d age, the compressive strength of the concrete with 25% aeolian sand replacement was 1.02, 1.08, 1.11, and 1.19 times that of ASC-0, ASC-50, ASC-75, and ASC-100, respectively. SEM observations showed that microcracks and pores gradually decreased with curing age, and ASC-25 exhibited superior compactness among all mixtures. The T₂ spectrum displayed three to four peaks, with the first peak as the dominant component. As the curing age increased, the proportion of the first peak area gradually increased in all groups. At 14 d age, the first peak proportions of ASC-0, ASC-25, ASC-50, ASC-75, and ASC-100 were 89.7%, 92.68%, 88.74%, 86.66%, and 86.13%, respectively. The proportion of harmless pores gradually increased in each group. For ASC-25, the harmless pore proportion was 43%, 48%, 60%, 63%, and 66% at 7, 14, 28, 56 d, and 84 d, respectively. The internal pore structure of the concrete gradually became denser. For ASC-25, the bound fluid saturation values were 91.51%, 92.72%, 94.53%, 95.21% and 96.37% at 7, 14, 28, 56 d, and 84 d, respectively, with corresponding porosities of 3.00%, 1.65%, 1.25%, 1.22%, and 1.04%, respectively. [Conclusion] The gray correlation analysis indicates that bound fluid saturation and the proportion of harmless pores are strongly correlated with compressive strength, with correlation coefficients exceeding 0.8. The compressive strength predicted by the GM(1,3) model closely matches the experimental results, with a maximum residual of 0.44 MPa, and the relative errors are all within 5%. The established GM(1,3) model can effectively predict the compressive strength of aeolian sand concrete at different curing ages, providing a reference for practical engineering applications.