The novel mixed ionic-electronic conductors Sm0.9Ca0.1Al1-xMnxO3 (SCAM, x= 0.1—0.5) were prepared by the organic gel method combined with solid state sintering technology. The thermal decomposition and phase inversion process of the gel precursors, crystal strucutres and phase stability of the sinters were studied by using thermogravimetric and differential thermal analysis (TG-DTA) and X-ray diffraction. The electrical conductivities of sintered ceramics in both air and 5%H2/Ar were measured by the direct current four-wire method. The experimental results show that the well-crystallized nanopowders with tetragonal perovskite structure can be obtained after calcining the gel precursors at 900℃ for 5h, the phase stability of SCAM ceramics decreases with increasing Mn content under reduction atmosphere. The electrical conductivity of SCAM ceramics is dominated by p-type electronic conduction and increases with Mn content and temperature. The mechanism of electronic transport is the hopping of p-type small polaron. With increasing calcination temperature and prolonging holding time, both the electrical conductivity and relative density of SCAM9155 become large initially and then decrease. The SCAM9155 sample sintered at 1600℃ for 10h has the highest relative density of 98.2% and electrical conductivity reaching 7.30S/cm in air and 1.91S/cm in 5%H2/Ar at 850℃. The apparent activation energies for SCAM9155 in air and in 5%H2/Ar were calculated to be 0.273 and 0.371eV, respectively. The Ca- and Mn-substituted SmAlO3 with relatively high conductivity may be used as a potential anode material for solid oxide full cells (SOFCs).