A skin external preparation containing an ascorbic acid-2-phosphate derivative is characterized in that only a sodium ascorbic acid-2-phosphate-6-palmitate is formulated as the ascorbic acid-2-phosphate derivative, and the skin preparation further includes at least one betaine-type amphoteric surfactant selected from the group consisting of compounds represented by the following general formula (1) or (2) (wherein R1 represents a linear or branched alkyl group of 6 to 30 carbon atoms, and R2 represents a linear or branched alkyl group of 8 to 30 carbon atoms). R1&mdash；N+(CH3)2&mdash；CH2COO&minus；&emsp；&emsp；(1) R2&mdash；CONH&mdash；CH2&mdash；CH2&mdash；CH2&mdash；N+(CH3)2&mdash；CH2COO&minus；&emsp；&emsp；(2)
