The present invention relates to a method of preparing an ultra-light metal oxide-silica composite aerogel having high specific surface area and high pore volume and a metal oxide-silica composite aerogel prepared thereby. The preparation method according to the present invention may not only have good economic efficiency because production costs are relatively reduced in comparison to the related art, but may also effectively prevent the collapse of a pore structure by suppressing a shrinkage phenomenon during drying, and thus, a metal oxide-silica composite aerogel having ultra-light properties as well as high porosity characteristics, such as high specific surface area and high pore volume, may be prepared.