The invention discloses a dragon fruit jam and a preparation method thereof. The dragon fruit jam is prepared from the following materials in parts by weight: 100 parts of dragon fruit with peel, 60-65 parts of water, 5-15 parts of a
sweetening agent, and 0.3-0.7 parts of a
thickening agent. The preparation method comprises the following steps: removing thorns from the dragon fruit with peel, cleaning,
slicing,
grinding and stirring the dragon fruit to obtain dragon fruit pulp, completely dissolving the
sweetening agent and the
thickening agent, adding the dragon fruit pulp, uniformly stirring the pulp, conducting high temperature instant sterilization, cooling the sterilized pulp, then conducting
fermentation treatment, and conducting
microwave concentration, filling and ultrahigh pressure sterilization so as to obtain the dragon fruit jam. The dragon fruit jam disclosed by the invention is of a natural edible value and a natural medicinal value of the dragon fruit, is low in
sugar content, and can keep the natural
nutrition and the
flavor in the
raw material well by the adoption of the
microwave concentration technology and the ultrahigh pressure technology.