The invention discloses a mannan-oligosaccharide-containing juice beverage with a health function and a preparation method of the mannan-oligosaccharide-containing juice beverage. The mannan-oligosaccharide-containing juice beverage following raw materials in parts by weight: 8-15 parts of fruit and vegetable juice, 0.1-0.5 part of a suspension agent, 4-10 parts of mannan oligosaccharide, 0.03-0.08 part of acesulfame, 0.1-0.4 part of citric acid and 0.03-0.07 part of potassium sorbate. The preparation method of the juice beverage with the health function comprises the steps of weighing the raw materials, glue dissolving, sugar dissolving, mixing, acidizing and filling. The juice beverage has a health function factor, namely the mannan oligosaccharide, has the effects of being agreeable in sweetness, relatively low in calorie and capable of regulating intestinal microecology and is strong in fragrance and fine in taste. According to the preparation method, the operation is easy, and the preparation is convenient; the preparation method is suitable for being used in large-scale industrial production.