Abstract: An alumina-based ceramic tool material with low thermal expansion and a preparation process thereof, accordingly, the ceramic tool material may have both the high hardness of alumina ceramics after the hot pressing sintering, and reduces the thermal expansion coefficient of the overall ceramic material by adding the Sc2W3O12 as the negative thermal expansion phase, which improves the thermal shock resistance of ceramic tools in high-speed cutting engineering and meets the requirements of large temperature range during the machining of nickel-based superalloys. Moreover, the composite material does not use metal binder and has strong thermal stability even in the high-speed machining under extreme heat-force-chemistry coupling, so it has a high machining compatibility for nickel-based superalloys.