Abstract: To explore the changes law of coal holes permeability after fracturing under different temperature and impact loads, based on fractal theory and classical model, the static strain and dynamic strain of coal caused by limiting impact load and temperature are analyzed, and the permeability model of coal in composite field is derived, and the permeability changes with temperature and impact load during coal hole fracturing are understood by using impact-fracturing seepage experiments under different temperature-impact loads. The results show that when the pressure is less than 1.0 MPa, the permeability channel becomes narrow due to the influence of temperature-impact load, the coal permeability decreases gradually with the increase of impact load, and decreases and tends to be gentle with the increase of temperature; when the pressure is more than or equal to 1.0 MPa and less than 10.0 MPa, the impact load causes the penetration channels to become wider and number to increase, and the permeability increases approximatedly exponentially with the increase of the impact load; when the pressure is greater than or equal to 10.0 MPa, the impact load reaches the ultimate compressive load, the coal fracturing occurs, the impact energy is released, the fracture structure is stable, and the permeability tends to be stable; under the action of composite field, coal hole impact fracturing goes through two stages: sensitive temperature penetration and sensitive impact load penetration; the calculated values of the new model are basically the same as those of the test, and the change law of the fracture permeability of coal holes under different temperature-impact loads is better presented; under the action of small impact load, the permeability of coal fractured by coal hole decreases, producing a slippage effect; when the impact load reaches the ultimate tensile load of coal, radial and circumferential fractures occur inside the coal, the slippage effect is weakened, and the permeability increases.