The invention relates to the technical field of food processing and in particular relates to a preparation method of multi-purpose rose flower sugar, which is wide in application range and can keep the aroma, the color, the nutrition and the medicinal value of roses for a long term. The preparation method comprises the steps of washing, soaking, cutting, mixing, fermenting and turning a bottle, and specifically comprises the following steps: washing picked fresh rose petals with clear water, dewatering, soaking in a citric acid water solution, cutting the soaked rose petals, mixing with white granulated sugar, and fermenting to prepare the multi-purpose rose flower sugar. The rose flower sugar is easy and convenient to prepare, is bright red and attractive in color, keeps the original aroma and the medicinal value of rose flowers, and is excellent in mouth feel and long in storage time.