The electrical properties of La(l-x)Sr(x)CoO(3) prepared by conventional solid state reaction were investigated. La(l-x)Sr(x)CoO(3) powder with desired ratio could be obtained by heat treatment for 15h at 1000 in the range of 0≤x≤0.3, but un-reacted compound was detected in the range of x≥0.4. The Seebeck coefficient and electrical conductivity for La(l-x)Sr(x)CoO(3) specimens (0≤x≤0.3) sintered at 1250~ 1350℃ for l0h in air were measured. The electrical conductivity for x=0 specimen increased with temperature, that is, exhibited the typical semiconducting tendency, and the Seebeck coefficient was positive, decreased rapidly with temperature. In the case of x=0.1 specimen, electrical conductivity increased slightly with temperature, showed a maximum value and decreased slightly with temperature, that is, exhibited semi-metallic tendency. On the whole, electrical conductivity for 0≤x≤0.1 specimens would be affected more by cooling rate than sintering temperature. On the other hand, electrical conductivity for x≥0.2 specimens exhibited the typical metallic tendency.