The invention belongs to the technical field of wine making, and particularly relates to a preparation method of pitaya and thorn pear fruit wine. The preparation method includes the following steps of (1) raw material processing; (2) juice extraction; (3) fermentation broth adjustment; (4) low temperature fermentation; (5) aging; (6) blending; and (7) filtering and bottling. According to the preparation method of the pitaya and thorn pear fruit wine, pitaya and thorn pear are used as raw materials, for the pitaya, pitaya juice is obtained through peeling, juicing and enzymolysis, the pitaya juice is mixed with enzymolysis thorn pear juice, brewing steps such as mixed fermentation, aging, fining, pouring, blending and filtering and bottling are performed, and the pitaya and thorn pear fruit wine is obtained, the obtained pitaya and thorn pear fruit wine is red in color and pure, the wine liquor is clear and transparent, the flavor is rich, the wine body is full, the sour taste and theastringent taste are balanced, the content of betaine is better than that of pure fruit wine fermented by pitaya, nutrition is rich, a brewing method is simple, the cost is low, and industrializationis easy.