Structural change and conductivity properties according to strontium content in La1-xSrxMn0.8Cu0.2O3-δ (LSMCu, 0.1≤x≤0.4) were investigated. La1-xSrxMn0.8Cu0.2O3-δ powders were prepared using the EDTA-citrate complexing process, which is one of sol-gel method, to synthesis of nano sized non-stoichiometric compound. X-ray diffraction (XRD) of the calcined and sintered powders was performed at room temperature in the 2θ range from 20° to 80°and the lattice parameters were refined by Rietveld analysis. The synthesized LSMCu powders were a pure perovskite phase, whereas the composition with LSMCu0.4 has second phases in grain boundary. The unit cell volumes decreased with increasing Sr2+ content because substituted Sr ions cause an increase in Mn4+ ions, which has a smaller ionic radius than Mn3+. The electrical conductivity measured by 4-probe DC measurement also improved with increasing Sr addition in 0.1≤x≤0.3, revealing a small polaron hopping mechanism. Thermal expansion coefficients compared with that of LSM and YSZ were 11.1 ~ 12.5 x 10-6/K. These values are suitable using for cathode material. X-ray photoemission spectroscopy (XPS) was carried out to invesigate to oxidation state of B-site elements. The oxidation state of Mn ions from Mn3+ to Mn4+ increased with the addition of Sr ions in 0.1≤x≤0.3 but the oxidation state of Cu ions was unchanged in 0.1≤x≤0.3. The addition of Sr ions in the A-site of LSMCu can lead to a contraction of the lattice volume because of the decreased Mn-O bond length and increased Mn4+ ions, which can enhance the electrical conductivity to make more hopping site of electons. Also, the polarization resistances of LSMCu0.1~0.4 were investigated by impedance analysis. The polarization resistance values of LSMCu0.3 and LSMCu0.4 were 1.60 Ωcm2 and 26.48 Ωcm2. The polarization resistance of LSMCu0.4 was higher than that of other compositions because densification in LSMCu0.4 can reduce triple phase boundary between cathode and electrolyte.