The present invention relates to a method for preparing unsaturated alcohol through selective hydrogenation of alpha,beta-unsaturated aldehyde. A purpose of the present invention is to solve the problems of low production capacity, low raw material conversion rate, low product selectivity and different separation between the catalyst and the product in the prior art. The technical scheme of the present invention comprises that the method for preparing the unsaturated alcohol through the selective hydrogenation of the alpha,beta-unsaturated aldehyde is used, the alpha,beta-unsaturated aldehyde and hydrogen are continuously introduced into a fixed bed reactor, and are subjected to a continuous selective catalytic hydrogenation reaction on a catalyst under a selective reaction condition, the generated product is subjected to gas-liquid separation and rectification to obtain an unsaturated alcohol product and unreacted methacrolein, and the hydrogen obtained through the gas-liquid separation and the unreacted alpha,beta-unsaturated aldehyde obtained after the rectification are recycled. With the technical scheme of the present invention, the problems in the prior art are well solved. The method of the present invention can be used for the preparation of the unsaturated alcohol through the selective hydrogenation of alpha,beta-unsaturated aldehyde.