The present invention belongs to the technical field of beverages, and relates to a probiotic fermented fruit and vegetable puree composition containing active bacteria and its preparation method. The composition containing active bacteria is obtained by fermenting fruit and vegetable puree with Lactobacillus casei NCU215. The probiotic fermented fruit and vegetable puree has the following characteristics: the probiotic fermented fruit and vegetable puree may generate a natural mellow sour, effectively remove an astringency in fruit and a wild Artemisia flavor in vegetable, and neutralize an unpleasant sour in the fruit; with probiotic fermentation, the present invention may improve a content of amino acid in the fruit and vegetable by 20% or more, generate multiple aromatic substances, improve a flavor substance by 30% or more, and effectively improve a taste and a mouthfeel of the product; the present invention prolongs a shelf life of the product and prevents rot.