The invention discloses a preparation method of calcium-rich Chinese dwarf cherry clear juice. The preparation method comprises the following steps: selecting mature Chinese dwarf cherries, cleaning, automatic coring, immediate and quick freezing and storing the mature Chinese dwarf cherries in an environment of -20 DEG C, naturally unfreezing, squeezing the mature Chinese dwarf cherries to obtain a Chinese dwarf cherry puree; adding pectinase into the puree to enzymatically decompose the puree, so as to obtain a Chinese dwarf cherry raw juice; adding chitosan and xanthan gum into the raw juice to perform chemical precipitation, filtering the raw juice through a membrane, so as to obtain a Chinese dwarf cherry clear juice; adding calcium carbonate into the clear juice to fully react with organic acid in the juice and form calcium malate, calcium citrate or calcium citric acid-malic acid chelate, allowing the juice to be at the still state after the reaction ends, obtaining supernatant to obtain a clear type calcium-rich Chinese dwarf cherry raw juice; adding sugar into the raw juice and blending, so as to allow the raw juice to be at a proper sugar-acid ratio; and finally sterilizing and filling, so as to obtain the calcium-rich Chinese dwarf cherry clear juice. The Chinese dwarf cherries with high concentration of titratable acid are processed by the method, so as to maintain the inherent flavor of Chinese dwarf cherries to the maximum limit, the calcium content in the products reaches 55-60mg / 100ml and compared with the prior art, the calcium content is increased by more than 4 times, the consumption of the sugar is reduced by more than 30%, the processing cost is reduced, and the preparation method is in line with the mainstream of low sugar food processing.