Abstract: The instant disclosure discloses a method for preparing 3-hydroxybutyrate salts, which includes: (1) providing ethyl 3-hydroxybutyrate or methyl 3-hydroxybutyrate, and hydrolyzing through a basic catalyst to obtain 3-hydroxybutyric acid; (2) making 3-hydroxybutyric acid reacted with an inorganic base to give 3-hydroxybutyrate. The instant disclosure adopts salt formation in water to make the reaction proceed more thoroughly, and also to save reaction time, to reduce energy consumption and material loss, to improve product yield and to lower production cost. The concentration process of the roughing (i.e. crude preparation) of 3-hydroxybutyrate is omitted.