The invention relates to a medicine which is used for treating acnes of young people and has a skin whitening effect and a preparation method thereof. The medicine comprises the following raw materials by weight: 40 to 60 grams of dry peach flower, 5 to 15 grams of angelica dahurica, 10 to 30 grams of tuckahoe, 20 to 40 grams of wax gourd seed, 20 to 40 grams of bitter almond kernel, 10 to 30 grams of fresh aloe gel, 5 to 15 grams of honey, 4 to 6 grams of pure glycerol, 5 to 15 grams of pure milk and 40 to 60 grams of vanishing cream. The preparation method comprises the following steps of: crushing the dry peach flower, the angelica dahurica, the tuckahoe, the wax gourd seed and the bitter almond kernel into 200-mesh fine powder, stirring to form paste by using the vanishing cream, adding the fresh aloe gel, the pure glycerol, the honey and the pure milk, and stirring to form paste. The medicine has the effects of cleaning skin dirt, clearing away heat, easing paining, relieving itching, resisting inflammation, removing vivotoxin, improving local blood circulation, promoting cell regeneration, softening skin stratum corneum, astringing, preserving moisture, moistening and nourishing, and is absorbed by local mucous membranes without the supersession of liver and kidney, so that medicinal potency reaches lesion sites directly to achieve the effects of easing pain, resisting inflammation, expelling toxin, fading black spots and scars and beautifying.