Effervescent skin external agent

The present invention at a low cost, that the user is to provide easy to handle external preparation for skin. A skin external preparation of the present invention, at least, a effervescent skin external agent having a solid acidic substance, and a solid carbon dioxide generating material generating carbon dioxide gas reacts with the acidic substance Te, further, the polysaccharide or derivative thereof containing at least one, is mixed with water-containing material at the time of use of the external preparation for skin. .BACKGROUND