Magnetic and electric properties of LaCoxMn1-xO3 (x=0.0, 0.1, 0.3, 0.5, 0.7, 0.9, 1.0) compounds were measured by applying the Superconducting Quantum Interference Device (SQUID) in the magnetic fields of 0 and 5 tesla at low temperatures. Respective atomic valences and the fraction of Co and Mn ions were also examined by an X-ray Photoelectron Spectroscopy (XPS) method at room temperature. Discrepancies in the electric resistivity (Magnetoresistance) of the compounds under the conditions with and without an applied magnetic field decreased with an increase of Co ion, and the maximum point of each agnetoresistance vs. temp. curve corresponded with the Curie temperature of transition from paramagnetic to ferromagnetic. Judging from the values of the effective magnetic moment obtained from Curie constant and as a result of deconvolution of the XPS spectrum, it was found that Co and Mn ions in the compounds coexisted respectively at the mixed valence states. The electron configuration of the former ion was low spin states of CoII+(t2g6eg1) and CoIII+(t2g6eg0), whereas, that of the latter ion was high spin states of Mn3+t(t2g3eg1) and Mn4+(t2g3eg0). It is probable that, in the present system compounds, the ferromagnetic double exchange interaction between Mn3+ and Mn4+ ions dominates over that between CoII+ and CoIII+ ions.