Abstract: Coal gangue sintered composite insulation block is a kind of energy-saving wall material, which has the advantages of light weight, high strength and good insulation performance. In order to study the compression performance of coal gangue sintered composite insulation block, two groups of 12 specimens of coal gangue sintered composite insulation block masonry were studied, and the failure characteristics and mechanical properties of sintered gangue composite insulation block and ordinary mortar and gypsum mortar masonry specimens were analyzed. The results showed that the local failure of sintered gangue composite insulation block caused the overall instability and failure of the masonry specimen, the compressive strength of the masonry was less than that of the block, and the test value was less than the calculation value in GB 50003-2011. Based on the test data, the stress-strain relation curve was obtained, and the proposed expression of stress-strain relation and the recommended value of elastic modulus of masonry were proposed through the method of analysis and comparison.