Cr2AlC thin films are deposited on MgO (100) and Al2O3 (0001) substrates with reactive radio frequency (RF) magnetron sputtering for the first time. Single phase Cr2AlC films are synthesized at a substrate temperature of 480°C and deposition power of 70W, with a preferred orientation. The film is polycrystalline with a dense microstructure. The preferred orientation disappears and AlCr2 impurity emerges as the temperature and sputtering power rise during the deposition. When the sputtering power is 90W or higher, the phase becomes totally AlCr2 due to C loss. The Cr2AlC phase is stable in vacuum for temperatures up to 700°C, but the phase starts to decompose into Cr7C3 at 800°C.