The invention relates to a high closing pressure extra-deep oil well and an extra-deep gas well, and pressing crack driving adopts high density and high strength pressing crack propping agent. The invention is characterized in that the composition is as follows: 100 parts of non-annealing bauxite with more than or equal to 75 percent of Al2O3, and 3 to 8 parts of MnO2, and 1 to 5 parts of ZrO2, the apparent density after balling is fired is 3.40-3.55 kg/cm <3>, the anti- fragmentation capacity under 86 MP pressure is more than or less than 5 percent (20/40 meshes), the main chemical composition is 78 to 85 wt percent of Al2O3, 2 to 5 wt percent of MnO2, 78 to 85 wt percent of Al2O3, 2 to 5 wt percent of MnO2, and 2 to 4 wt percent of ZrO2. The propping agent of the invention has small composition material, simple preparation, low cost and good economical efficiency, the apparent density reaches the density limiting of 3.40 to 3.55 g/cm <3>, the compressive strength is high, the propping agent has 20/40 meshes of grain size, the anti-fragmentation capacity is (SY/T5108-2007) 86 MPa which is more than or less that 5 percent, the maximum can reach 100 MPa which is more than and less than 8 percent, the invention can satisfy the pressing crack driving of the high pressure extra-deep oil well and the extra-deep gas well under the formation closing pressure more than and equal to 86 MPa, the formation crack is supported under the high pressure, and the flow conductivity can be greatly improved.