We have developed three methods of solid oxide electrochemical doping (SOED). SOED 1 consists of an anode/M-beta "-Al2O3/ceramics/M’-beta "-Al2O3/cathode system, where the Mn+ cation can be doped into ceramics together with substitution of a cation (Nm+) in the ceramics (electro-substitution mechanism). SOED 2 consists of an anode/M-beta "-Al2O3/ ceramics/Y-stabilized ZrO2/cathode system, where the Mn+ cation can be injected into the ceramics together with the injection of an oxygen anion (electro-bi-injection mechanism). SOED 3 consists of an anode/M-beta "-Al2O3/ceramics system, where the Mn+ cation can be directly injected into the ceramics. SOED 1 and 2 are very useful doping methods, because various cations can be easily doped into all of the functional oxide ceramics under electric force. Some results in SOED methods are reported.