Abstract: The anode process of solid state in situ electrochemical reduction from TiO2 to Ti was studied by cyclic voltammetry and the whole electrode process was analyzed. The results show that the anode process is a one-step reversible oxidizing reaction of two-charge with the products undissolved and CO2 is produced at carbon anode. The anode reactions can be expressed as C+2O^2--4e=CO2. The general electrode reactions can be expressed as 2TiO2+C=2TiO+CO2, 2TiO+C=2Ti+CO2, 2CaO+C=2Ca+CO2. The Ca produced at cathode can also continue the thermo-reduction reactions. The reduction of TiO2 to Ti is attributed to the directly electrochemical reduction of TiO2 and calciothermic reaction when there is a few amount of Ca in the CaCl2 melt.