PURPOSE: To laxative food, containing alginic acid, a flavonol (glycoside) such as kaempferol or (iso)quercetin and edible alkali (earth) metal ion or salt as essential components, and capable of improving chronic constipation symptoms.

CONSTITUTION: A laxative food containing (A) alginic acid contained in brown algae, in large amounts (B) a flavonol (glycoside) such as kaempferol, quercetin and isoquercetin contained in grapes or figs and (C) an edible alkali (earth) metal ion and/or salt such as common salt, potassium chloride or calcium chloride as essential constituent components. Preferably, the above-mentioned components (A), (B) and (C) are fragments, powder or aqueous extract of a natural plant body containing the components.