Transparent conductive TiO2 films doped with Ru and Ta were prepared on SiO2 glass substrates by the sol-gel method using Ti(OC3H7i)(4) solutions with HCl, HNO3 or diethanolamine (DEA) as a catalyst. The films were anatase when HCl or HNO3 was added to the solution. The solution preparation condition, solution composition, dopant content and hear-treatment temperature all affected the electrical resistivity of the resultant films. There was a clear tendency for the film resistivity to become lower when the dopant solution was refluxed and HCl was used as the additive. The resistivity decreased with increasing Ta content, but decreased with increasing Ru content. Most of the films showed resistivity minima at a heat-treatment temperature of 700 degrees C. The lowest resistivity of 10 similar to 100 Ohm cm was attained when only Ta was used as a dopant.