The object of the present invention is to improve the solidification point and the hardness of a soap of the fatty acid soap series wherein the percentage of potassium used as the counter ion is large. The solid soap of the present invention to achieve the above-described object is characterized by comprising 1 to 5 mass % of a betaine, and in that sodium and potassium are contained as the fatty acid counter ion, and potassium is 20 mole % or more of the counter ion.
