The invention discloses a compound fruit and vegetable enzyme and a preparation method thereof, wherein the preparation method comprises the specific steps: (1) mixing and crushing fruits and vegetables, wherein the fruits and vegetables are composed of the following raw materials: 10-30 parts of carrot, 10-30 parts of burdock, 10-30 parts of Chinese yam, 10-30 parts of raw ginger, 10-30 parts of cucumber, 10-30 parts of broccoli, 10-30 parts of aloe, 10-30 parts of spinach, 10-30 parts of pumpkin, 10-30 parts of apple, 10-30 parts of raw pear, 10-30 parts of grapefruit, 10-30 parts of pineapple, 10-30 parts of red jujube, 10-30 parts of hawthorn, 10-30 parts of papaya, 10-30 parts of orange, 10-30 parts of peach, 10-30 parts of lemon, 10-30 parts of plum, 10-30 parts of grape, 10-30 parts of mulberry, 10-30 parts of blueberry, 10-30 parts of strawberry, and 10-30 parts of durian; (2) adding an enzyme live keeping agent; (3) adding a bacterial fluid, sealing, and fermenting; and (4) filtering. The compound fruit and vegetable enzyme has comprehensive various extracellular enzymes, has strong vitality, can make in-vivo blood become slightly alkaline, eliminates waste in a body, maintains the balance of intra-intestinal bacteria, strengthens cells, promotes digestion, strengthens resistance, and makes a body keep balanced in various aspects.