<p>This study investigated the influence mechanism of igneous intrusion on coal spontaneous combustion characteristics, focusing on the metamorphic coals from Daxing Coal Mine. The pore structure and oxygen adsorption capacity of tectonic coal were systematically characterized using low-temperature gas adsorption and chromatographic oxygen adsorption methods. Oxidation kinetic experiments were conducted to obtain oxygen consumption capacities under two different initial adsorption states. A novel method is proposed to calculate the critical temperature (<i>T</i>_b) for the transition from dominant physisorption to prevailing chemisorption during the low-temperature oxidation process. The results demonstrated that: (1) the <i>T</i>_b of contact metamorphic coal (DX#1) reached 72.11°C due to the depletion of active radicals, while for thermally evolved coal samples DX#2–DX#6, <i>T</i>_b increased from 58.71 to 75.33&#xa0;°C with sampling distance; (2) the variation pattern of <i>T</i>_b aligned with the crossing-point temperature of methane-containing coal, effectively characterizing the alterations induced by igneous intrusion in the low-temperature oxidation process; (3) synergistic experimental–numerical investigation revealed that coal samples proximal to intense thermal activity zones demonstrate enhanced pore capacity for oxygen adsorption and increased diffusion coefficients, thereby promoting efficient oxygen-residual methane displacement within the coal matrix. These findings demonstrate that the impacts of igneous intrusion are multifaceted, whereby the synergistic effects of multiple controlling factors establish a positive correlation between spontaneous combustion propensity and thermal evolution intensity. This research provides crucial theoretical foundations for developing effective fire prevention strategies in mining areas affected by igneous intrusions.</p>