The invention provides a medicated diet for conditioning phlegm-dampness constitution, and a preparation method thereof. The medicated diet comprises such components as Chinese-date, radix astragali preparata, ginseng, roasted rhizoma atractylodis macrocephalae, poria cocos, roasted rhizoma atractylodis, agastache rugosus, roasted semen coicis, lotus seed, gorgon fruit, Chinese yam, roasted white hyacinth bean, fructus amomi, immature bitter orange, platycodon grandiflorum, costustoot, prepared liquorice root, fingered citron, perilla stem, fructus cannabis, radix sophorae flavescentis, folium artemisiae argyi, scorched medicated leaven, scorched malt, scorched hawthorn fruit, loofah sponge, ricepaperplant pith, tangerine, caulis bambusae in taeniam, fructus perillae, semen raphani, wax gourd kernel, leonurus, rhizoma alismatis, smoked plum, longan aril, ginger, brown granulated sugar and starch syrup. The natural food materials and medical and edible materials and substances for healthcare food are taken as the major raw materials of the medicated diet, and therefore, the medicated die has the effects of replenishing qi to invigorate the spleen, tonifying the lung and the kidney, clearing damp and promoting diuresis, clearing damp and reducing phlegm, promoting the circulation of qi and regulating the flow of qi, regulating the qi function of a human body and the like, and has an excellent effect of conditioning the phlegm-dampness constitution.