Composites　of　Al2O3　and　3%　(in　mole)　yttria-stabilized　tetragonal　zirconia　polycrystals　(3Y-TZP)　were　prepared　by　liquid　phase　sintering　with　the　addition　of　TiO2-MnO2　and　CaO-Al2O3-SiO2　glass　as　sintering　flux.　The　effects　of　sintering　flux　on　the　densification,　microstructure　and　mechanical　properties　of　the　composites　were　investigated.　It　is　found　that　apart　from　partial　solid　solution　of　TiO2　into　the　ZrO2　grains　the　additives　are　existed　mainly　as　grain　boundary　glass　phase,　which　affects　the　distribution　of　Y2O3　in　ZrO2　grains.　The　densification　of　the　composites　is　greatly　improved　by　the　additives.　Meanwhile　the　sintering　temperature　is　obviously　decreased,　resulted　in　obtaining　fine　grain　structure　and　excellent　mechanical　properties　of　composites.