New　lithium　fast　ion　conductors　of　Li1.2+x-yAl0.1+xTi1.9-x　Si0.1SyP2.9-yO12　based　on　LiTi2(PO4)3　have　been　prepared　by　high　temperature　solid　state　reaction　using　refined　natural　kaolinite　as　a　starting　material.　X-ray　powder　diffraction　analysis　indicates　that　a　phase　with　Nasicon-like　structure　exists　in　the　composition　range　of　x　≤　0.30,　y　<　0.2　+　x.　AC　impedance　measurements　show　that　the　initial　composition　with　x=0.20,　y=0.20　possesses　the　highest　ionic　conductivities　of　6.01　×　10-5　S/cm　at　room　temperature　and　1.11　×　10-2　S/cm　at　573　K　with　activation　energy　of　28.6　kJ/mol　in　the　temperature　range　of　373-573　K,　DC　polarizing　measurement　shows　that　its　decomposing　voltage　is　3.1　V.