In hydrothermal reactions at 260-300 degrees C, ketones can be reduced into corresponding alcohols by hydrogen transferring from another alcohols or formic acid without a metal catalyst. When using formic acid as a hydrogen donor, the yield of alcohols at respective better conditions was considerably high at a much lower ratio of hydrogen source to ketones compared to traditional Meerwein-Poundrof-Verley (MPV) reduction, reaching 60% for isopropanol from acetone and 70% for lactic acid from pyruvic acid. The proposed possible mechanism for the hydrogen transfer reduction of ketones in high-temperature water (HTW) is similar to the pathway elucidated in the traditional MPV reduction via a transition state. Rather than metal-alkoxides catalysts in MPV reduction, water molecules in HTW as a catalyst may directly participate in the transition state by making a hydrogen-bond ring network with three molecules, that is, ketone, formic acid, and water.