Multilayered mullite/Mo cermet functionally gradient material (FGM) was fabricated through a powder stacking process and sintering in vacuum up to 1500°C. The composition distribution, microstructure and microhardness of the FGM were analyzed. The results indicated that the mullite/Mo FGM was well densified with composite graded distribution and there was no new phase appeared. The microhardness of the FGM increase from 467HV to 1543HV, the density from 2.919 to 7.106 g/cm3 as the content of mullite increase from 20% to 80%. The relative density exceeded 90% as the content of mullite reached 80%. Thermal shock test showed that the cracks passed through the joint without deflection.