Blending coal is a promising way to adjust ash fusion characteristics for coal with a high ash fusion temperature (AFT). Ash fusion characteristics of coal samples and their variation behaviors through coal blending were discussed. The regulation mechanism was investigated by an X-ray powder diffractometer with the assistance of normalized reference intensity ratio software and a scanning electron microscopy analyzer equipped with energy-dispersive X-ray spectrometry. The results show that the variations of ash fusion behaviors were diversified in blending coal type and the mass ratio. It was found that the optimized blending mass ratio was in the range of 30-50% for three blending coals to meet Liangbaoshi (LBS) coal gasification in an entrained-flow bed gasifier (EFB). Avery high melting point (MP) mullite formation at a high temperature makes the LBS AFT higher. With an increasing blending coal mass ratio, the formations of low-MP hercynite, anorthite, and gehlenite, their low melting eutectics, and these contents increase, resulting in the APT decrease of mixed ashes. The content of an abundant amorphous matter increases with a low-AFT coal mass ratio increase, also leading to the APT decrease.