The invention discloses a method for preparing raspberry enzyme, which comprises the steps of pretreating raw materials, inoculating microorganisms, continuously fermenting for three times, monitoring the fermenting process, carrying out natural precipitating, transferring and clarifying by standing, then filtering by utilizing a 200nm filter material, and filling to obtain the raspberry enzyme. According to the preparation method, three microorganism strains are adopted for fermenting, each microorganism has specific metabolite and metabolic pathway, juice ingredients can be metabolized and transformed into enzyme, organic acid, minerals, small molecule peptides and soluble cellulose, the fermenting process is strictly monitored, the foundation is laid for improving the enzyme quality, the raw materials are reasonably combined, the fermenting process is simple and controllable, the fermentation is complete, and the safety is high. The prepared raspberry enzyme is rich in nutrition, has a remarkable immunity adjusting function, and has functions of resisting radiation injury and oxidation, improving memory, cancer and tumor, relieving senescence and the like.