A positive electrode for use in a lithium battery using water as a dispersion medium, not causing a problem of deteriorating the battery performance due to corrosion of a collector or the like and not forming unevenness on the coating surface, as well as a lithium battery using the positive electrode, the positive electrode used being formed from a positive electrode paste containing a positive electrode active material represented by the following formula (I), a binder ingredient comprising a water dispersible elastomer and a water soluble polymer as a viscosity improver, water as a dispersion medium and a dispersing agent: LixMPO4  (I) (in the general formula (I) above, M represents a metal atom containing at least one of metal atoms selected from the group consisting of Mn, Fe, Co, Ni, Cu, Mg, Zn, V, Ca, Sr, Ba, Ti, Al, Si, B and Mo, and 0