Breakfast cereal is a very popular food product recommended by dieticians. All you need to prepare a muesli meal is to add some milk, yoghurt or juice. The objective of this study was the comparison of the ingredient composition of the conventional and organic muesli cereal and the assessment of marking and labelling used on organic and conventional muesli packaging. On the basis of this study a range of conclusions has been drawn in terms of improper labelling of muesli cereal. The major shortcoming of the improper labelling consists in the lack of information about the allergens, instructions how to prepare, incorrect expiry date note saying “use before the end of” instead of ”use before”. Organic muesli cereal did not contain any additions and its food ingredients included only cane sugar, salt and honey, and, in most of the cases, these components were also of organic origin.