<p>A permeability estimation of fractures during underground fluid movement and dissolution process remains a significant challenge. This study experimentally explores the effects of acid dissolution on the geometry and permeability of limestone fractures. A series of limestone fractures is immersed in acidic solutions for 72&#xa0;h under varying pH and temperature conditions, and its morphology and void geometric structure are obtained through X-ray computed tomography system. The chemical dissolution of fracture surfaces follows Arrhenius-type kinetics, exhibiting both pH and temperature dependence. The effects of strong acid, moderate acid and weak acid on micro-morphology evolution of fractures are identified. The experimental results demonstrate that, under ambient temperature, the magnitude of changes in the dual fractal characteristics (surface fractal dimension <i>D</i>_<i>f</i> and curvature fractal dimension <i>D</i>_<i>t</i>) of fracture surfaces gradually decreases as solution acidity weakens. In addition, temperature increases further intensify acid dissolution by accelerating reaction rates, raising the formation of more complex dissolution morphologies and resulting in more pronounced enhancements in fracture surface roughness and aperture expansion. Two empirical relationships between fractal dimensions, aperture, and cumulative acid consumption are established by fitting the experimental data, capturing the evolution of fracture geometry under acidic dissolution. A novel fractal-based permeability model incorporating geometric changes during chemical dissolution is further proposed and validated through experimental evidence from Noiriel et al. (<CitationRef CitationID="CR33">2013</CitationRef>). The results reveal a distinct time-dependent enhancement in permeability, demonstrating strong correlations with both temperature fluctuations and initial pH conditions.</p>