The invention relates to a preparation method of a palladium-charcoal catalyst for an alpha-alkylation reaction of ketone and alcohol and a preparation method thereof. The preparation method comprises the following steps: acidifying and washing a carrier; adsorbing a palladium salt component: dissolving palladium salt with sodium carbonate to adjust the pH value to 5 and then mixing the solution with activated charcoal slurry; reducing: reducing palladium hydroxide adsorbed on the activated charcoal to metal palladium; washing the metal palladium with deionized water to be neutral and removing chloride ions to obtain a palladium-charcoal catalyst precursor product; and performing surface hydrophobic treatment on the palladium-charcoal catalyst, treating the palladium-charcoal catalyst precursor product in a sodium borohydride alkaline solution for a certain time, and washing the solution to be neutral to obtain a hydrophobic palladium-charcoal catalyst. According to the catalyst provided by the invention is used for the alpha-alkylation reaction of ketone and alcohol, and generation of a byproduct, namely coupled alcohol, is reduced.