The invention provides a formula capable of effectively improving the quality of lauric acid cocoa butter substitute (CBS) chocolate. According to the formula, the chocolate comprises the following components in percentage by weight: 30 to 45 percent of fat, 10 to 15 percent of cocoa powder, 15 to 30 percent of white granulated sugar, 5 to 25 percent of cane sugar substitute, 10 to 20 percent of defatted milk powder and 0.3 to 0.5 percent of emulsifying agent. The invention also provides a method for preparing the chocolate by using the formula. The chocolate has the advantages of effectively solving the problem that the traditional chocolate is easy to frost, endowing the chocolate with a constant smooth surface, comprising rich probiotic factors and having nutritional and health-care functions, and having pleasant odour, refreshing mouthfeel and crisp character by a proper process.