Genetically modified (GM) organisms are used for production of GM food raw materials and food itself. This brings benefit to food production but also a certain health risk. The novel Czech food legislation requires labelling food containing more than 1 % of GM products. The methods of detection of GM products in raw and processed food are based on the determination of nucleic acids (PCR, analysis of RNA transcripts) or protein determination (transgene product activity, immunoassays). Certain types of GM products can be detected by chromatography or IR spectroscopy. All the methods have certain limitations (sensitivity, presence of inhibitors, etc.). This review summarizes application and suitability of the described methods for analysis of GM products.