<p>Red sandstone has significant applications in various fields such as construction, environmental protection, and civil engineering. The study of the synergistic response between the physical properties of red sandstone and its radon exhalation behavior is of great significance for understanding the radon migration mechanisms within geological formations and assessing the risks of radioactive gas in building engineering projects. Compressive tests were conducted on red sandstone from the Linyi region of Shandong Province under varying load intensities. Key physical parameters, including electrical resistivity, wave velocity, pore structure, and radon exhalation characteristics, were measured post-loading. The relationships between these parameters and radon exhalation behavior were analyzed to reveal the mechanisms driving radon exhalation changes during rock failure. The results indicate that as stress levels increase, the electrical resistivity, porosity, radon exhalation rate, and micropore fractal dimension initially decrease and then increase, reaching minimum values at 0.44 <i>F</i>_peak. In contrast, wave velocity and mesopore fractal dimension show an opposite trend, peaking at 0.44 <i>F</i>_peak. At 0.86 <i>F</i>_peak, the radon exhalation rate reaches a maximum value of 1.55 × 10^− 3 Bq/m²·s, representing a 41.76% increase compared to 0.15 <i>F</i>_peak. Furthermore, the radon exhalation rate exhibits a significant positive correlation with porosity, resistivity, and micropore fractal dimension, and a significant negative correlation with wave velocity. A strong linear relationship is observed between the radon exhalation rate and the parameters of porosity, resistivity, and wave velocity. The research findings provide important references for the rock radiation safety assessment of construction engineering and geological environmental studies.</p>