To solve the problem of the field application of downhole hydraulic fracturing technology due to the difficulty in sealing holes, this study analyzes the influence of special cement, expansion agents, stabilizers, and fiber material on basic properties, such as the setting time, fluidity, and compressive strength of high-pressure sealing materials through systematic tests based on a summary of conventional sealing materials. It was determined that with 20−30% special cement and 4% expansion agent added, and a fiber material length of 8 mm and volume of 1%, the high-pressure sealing material had high fluidity and a large expansion rate, demonstrating early strength. The bond performance of the high-pressure sealing material was tested through the variable-angle shear test. The relationship between the fractal dimension of the coal-rock mass around the borehole and the bond performance of the high-pressure sealing material was also explored.