Abstract: For the problem that low success rate of gas pressure test and unreliable measured values in nearly level drilling along the seam, adopting multi-aperture drilling process technology, we propose testing technology of gas pressure which use multi-aperture and cement mortar hole-sealing in nearly level drilling along the seam. We use two-level aperture to measure gas pressure from two nearly level drillings along the seam in the same geological unit, and the test results are 0.54 MPa and 0.50 MPa respectively. The result of indirect method is 0.49 MPa that is consist with the measured data and verify that the new testing technology of gas pressure is accuracy and applicability.