The first catalytic enantioselective aldol reaction of various unprotected carboxylicacids is described. In the presence of a chiral bis(phosphine oxide) as a Lewis base catalyst, carboxylicacids were activated with silicon tetrachloride to form the corresponding bis(trichlorosilyl)enediolates in situ, which subsequently underwent an aldol reaction with an aldehyde or a ketone to produce β‐hydroxycarboxylic