Abstract:The perovskite oxide La1-xSrxCoO3 ( 0≤x≤0.5) series were prepared under different sintering conditions by a standard solid-state reaction method. Crystal structure was determined by powder X-ray Diffraction and lattice parameters as a function of Sr-concentration x were obtained by using Rietveld method. The dc resistivity investigated in the temperature range of 80-300K indicates that, the electric properties exhibit a metal - insulator (semiconducting) (I-M) transition for 0.2