The invention discloses a preparation method of a novel vegetable and fruit fermented beverage. The preparation method comprises the steps of: firstly carrying out enzymolysis on mixed fresh juice of fresh vegetables and fruits after dilution and size mixing by adopting cellulase, fermenting by adopting a mixed lactic acid starter after adding sugar and corn oligopeptide as fermentation substrates and sterilizing, adding calcium carbonate when the pH reaches 4.0, and then inoculating leuconostoc mesenteroides for continuous fermentation; adding a feed supplement and sterilizing when the pH reaches 3.5, and then adding high-activity dry yeast for the fermentation for 2-3 days; and finally performing sterilization, centrifugation, homogenizing, blending, sterilizing and filling to obtain the novel vegetable and fruit fermented functional beverage. The enzymolysis is firstly carried out on a product by the cellulase, then lactic acid bacteria and saccharomycetes are utilized for the step-by-step fermentation of the mixed fresh juice of the fresh vegetables and fruits, and the corn oligopeptide is added to promote the growth and the metabolism of fermentation strains, so that the novel vegetable and fruit fermented beverage has clear composition of functional components, contains abundant oligopeptide, organic acids, reducing sugars, sugar alcohols and soluble dietary fiber, and integrates nutrition and health care, thus being a novel vegetable and fruit fermented beverage.