The　effects　of　the　rare　earth　oxide　on　the　thermodynamics　of　Al-Ti-C-RE　master　alloy　prepared　by　mixing　the　potassium　titanium　fluoride　and　carbon　into　aluminum　melt　were　studied　by　means　of　SEM,　EDS　and　DSC.　The　results　show　that　the　aluminothermy　reaction　of　the　Al　melt　and　K2TiF6　occurs　to　produce　the　TiA13　and　[Ti]　atoms.　Then,　based　on　the　aluminothermy　reaction,　the　rare　earth　oxide　Ce2O3　reacts　with　carbon　to　produce　the　carbothermy　reaction　and　abundant　CeC2　phases　form,　which　react　with　[Ti]　atoms　easily　to　produce　the　TiC　particles　and　[Ce]　atoms.　The　reacted　[Ce]　atom　is　a　kind　of　surface　active　elements,　and　easily　adsorbs　on　the　TiA13　phases　to　form　the　new　rare　earth　compounds　Al2Ti20Ce.　The　DSC　analysis　results　show　that　the　rare　earth　oxide　Ce2O3　has　spontaneous　carbo-thermal　reaction　at　1　120°C,　which　decreases　the　reacting　temperature　to　manufacture　Al-Ti-C-RE　master　alloys,　improves　the　wettability　between　carbon　and　aluminum　melts　and　promotes　the　formation　of　TiC　particles.