$LaMnO_3$ and A site substituted $La_{0.9}Sr_{0.1}MnO_3$(a=$5.33AA$, c=$13.27AA$), B site substituted $LaMn_{0.9}Cu_{0.1}O_3$(a=$5.52AA$, c=$13.31AA$) mixed oxides were prepared by Citrate sol-gel method. The powder X-ray diffraction patterns of these oxides were indexed with single phase hexagonal perovskite structures. According to the TRR result, oxygen stoichiometry of these oxides were oxidative nonstoichiometry as like $LaMnO_{3.16}$, $La_{0.9}Sr_{0.1}MnO_{3.10}$ and $LaMn_{0.9}Cu_{0.1}O_{3.14}$ Reduction reactions of un-substituted $LaMnO_3$ was two steps, but specific site(A site of B site) partially substituted $LaMnO_3$ oxides were procees to three reactions.