The contents of the dietary fibre in a cereal-fruit-vegetable snack according to the invention is large. Full fresh or deep-frozen fruits or vegetables included in the composition of such a snack comprise from 60 to 80% by weight of the total dough mass prior to the thermal treatment. Cereal bran comprise from 20 to 40% of the total dough mass prior to the thermal treatment. Additionally the snack is enriched with complementing additives in the form of vitamins, antioxidants, and flavour additives. A method of preparing such a snack consists in that cereal bran are extruded at a temperature from 100 to 160°C and under a pressure from 70 to 160 bar. Next they are dried up to a humidity from 3 to 6% and afterwards mixed in a heated drum mixer under pressure with full fresh or deep-frozen fruits or vegetables being at the same time heated till a temperature from 40 to 60°C is reached. The resulted mixture is disintegrated to an extent so as to maintain fragment of fruits or vegetables contained therein and formed into a thin band from 0.5 to 1 mm thick, which is spread on a drier belt and dried at a temperature from 90 to 130°C up to a humidity from 15 to 30%. The pre-dried mass is disintegrated to an extent so as to maintain fragments of fruits or vegetables and enriching additives such as vitamins, antioxidants and flavour additives are added to it, then the mass is mixed again and from it snacks of required shapes are formed and next dried at a temperature from 90 to 130°C till a humidity from 3 to 5 % of a final product is achieved.
