Abstract: Air entrained, super plasticized concrete having a maximum bubble spacing factor of 0.008 inch (ASTM Standard C 457) and a method for preparing such concrete are disclosed. The method includes the steps of adding an air entraining agent while mixing aggregates and water, adding during the mixing a small but effective quantity of a potassium salt of a fluorinated alkyl carboxylate having a high surface activity and a pH of 8-9, and then adding a super plasticizer to the resulting mix prior to placement. The air entrained concrete having the aforesaid bubble spacing factor contains a super plasticizer, a vinsol resin air entraining agent, and a potassium salt of a fluorinated alkyl carboxylate. The fluorinated alkyl carboxylate is present in an amount of one to two parts per 100 parts of the super plasticizer on a weight basis.