The invention relates to an areca-nut core substitute for areca-nut food and a preparation method thereof. The areca-nut core substitute is prepared by blending the following components in percentage by weight: 0 to 2 percent of sweetener, 0 to 20 percent of areca-nut core extract, 0 to 80 percent of dietary fibers, 1 to 80 percent of edible nut extract, 0 to 30 percent of creamer, 0 to 50 percent of coffee powder, 0 to 10 percent of table salt, 0 to 5 percent of foaming agent, 0 to 5 percent of flow aid, 5 to 90 percent of filler, 0 to 2 percent of essence and the balance of water. The areca-nut core substitute is prepared by mixing the components including the sweetener, areca-nut core extract, nut extract, coffee powder, creamer, dietary fibers, filler, water and the like, so when usedin areca-nut food, the product can provide strong natural nut fragrance and natural coffee fragrance when the areca-nut food is taken and can effectively inhibit areca-nut brine from retransferring. The areca-nut core substitute is mildew resistant.