Li0.24+2xLa0.59-xMxTiO3-LaPO4(M　=　K,　Na)　fast　ionic　conductor　was　synthesized　by　high　temperature　solid　state　reaction.　A.　C.　Impedance　measurements　show　that　the　compositions　of　system　have　better　conductivities　in　low　doping　content　of　Na+and　K+,　as　the　doping　content　increases,　the　conductivity　goes　down　in　Na+doping　system.　But　in　doping　K+system,　the　conductivity　goes　down　and　then　goes　up　with　the　increasing　content　of　K+.　The　activation　energies　of　different　doped　ions　are　about　20　kJ·mol-1in　the　temperature　range　of　25°C-400°C.　X-ray　powder　diffraction　shows　that　the　doped　Na+and　K+would　not　affect　the　structure　of　compositions　in　the　system.　The　main　phase　is　Li0.24+2xLa0.59-xMxTiO3perovskite　solid　solution,　LaPO4as　a　second　phase　also　can　be　found.　With　increasing　the　content　of　M　(x　＞　0.04),　unknown　phase　appears.　IR　measurement　also　indicates　that　the　structure　of　compositions　in　the　system　would　not　be　affected　by　doping　alkali　ion.