In view of the important industrial application value of alumina supports in the field of oil refining andreforming, it is of great significance to develop a simple and economical synthesis method for the hierarchicalporous alumina. Herein, the hollow microsphere alumina was hydrothermally synthesized withouttemplate. The surface of the hollow microsphere alumina supports has a raised fluffy structure, themicrosphere diameter is about 5 8 lm, and the thickness of the shell is about 1 lm. The morphologyevolution process from solid microspheres to core–shell microspheres with spindle-shaped nanoclusters,and then to hollow fluffy microspheres with protruding surface was observed by investigating the effectof hydrothermal synthesis temperature on the morphology of microspheres. Because of its specific morphologyand surface characteristics, the microsphere can better disperse the active component KW toprepare KW/Al2O3 catalyst and used in the thiolation to methyl mercaptan. Compared with our previouslyused catalysts prepared from commercial alumina, this KW/Al2O3 catalyst was not only able togreatly reduce the amount of active component, but also exhibited higher CH3SH selectivity. On the10KW/Al catalyst, the CH3SH selectivity reached 66.2 % at 340 C, which was about 10 % higher than thatof the previous commercial alumina catalyst. This work can provide theoretical basis and practical guidancefor the reasonable design of new alumina support and high efficiency methyl mercaptan catalyst.