In order to study the morphology and catalytic oxidation performance of LaMnO3 nanoparticles after A or B site doping , the sol-gel methods is applied, the La1-xSrxMnO3 and LaCuxMn1-xO3（x=0.1, 0.2, 0.3, 0.4, 0.5) nanoparticles are prepared. The diameter of particles and morphology-distribution of naniparticles with different doping amounts are analyzed by X-ray diffraction (XRD), scan electric microscope (SEM) and related software. With the framework of the experiment, the average diameter of particles is between 16-21nm with better chemical homogeneity and have higher surface area. At the same time, the catalytic oxidation of nanoparticle under different doping amounts is also studied. Tests results show that nanoparticle has excellent catalytic oxidation performance, and with the increase of doping amount, the catalytic activity of the particle increase first and decrease afterwards with the increase of A or B site doping amount, the best performance presents at X=0.2 of A or B doping concentration. The effect of lattice deformation arising from the dopants, which leads to the decrease of the catalytic performance, can not be ignored at higher doping concentration anymore. Under the same doping amounts, the catalytic performance of B-site doped is better than A-site.