As an essential layer system for shale gas exploration in southern China，the shale of the Longmaxi Formation in northeastern Chongqing has undergone multi-stage tectonic movement superposition and transformation，and its nano-pore structure and fractal characteristics have not been systematically explained. Through the observation of nano-pore morphology by field emission scanning electron microscopy （FESEM） and the quantitative characterization of pore structures based on Image J software，combined with the specific surface area，pore volume，and pore size distribution parameters obtained by low-temperature N₂ adsorption experiments，the FHH fractal model was used to calculate the pore fractal dimension. The fractal characteristics and influencing factors of nano-pores in the tectonically deformed shale of the Longmaxi Formation in the Dabashan foreland thrust belt in northeastern Chongqing were systematically revealed. The results show that the tectonically deformed shale of the Longmaxi Formation in the study area primarily develops organic matter pores，intergranular pores，and intragranular pores，with the reservoir space dominated by mesopores，accounting for an average of 59.30%. The calculation results of the FHH fractal model indicate that the low-temperature N₂ adsorption-desorption curve of the tectonically deformed shale of the Longmaxi Formation begins to show a hysteresis loop when the relative pressure P/P₀ = 0.45. Based on this，the fractal dimension D is divided into D₁ in the low pressure region（P/P₀ < 0.45）and D₂ in the high pressure region（P/P₀ ≥ 0.45）. The average D₁ is 2.609 0，and the average D₂ is 2.657 1，indicating that the nano-pores of the tectonically deformed shale have obvious fractal characteristics. With the increase in specific surface area and pore volume，the fractal dimension also increases；the pore structure becomes more complex，and heterogeneity is stronger. There is a significant positive correlation between the total organic carbon content and the fractal dimension，which confirms that the hydrocarbon generation and pressurization during the thermal evolution of organic matter promote the development of nano-pores. The quartz content is positively correlated with the fractal dimension，reflecting the protective effect of rigid minerals on pore structure. Clay minerals are negatively correlated with fractal dimension，indicating that plastic minerals reduce the complexity of pore structure through particle recombination under tectonic stress.