Food allergies are in increasing issue in food safety. Therefore; the evaluation and detection of food allergens become more and more important. To quickly and accurately detect food allergens is an urgent need. At present; the most common method used in allergen detection are immunological detection; mass spectrometry and SPR technology. However; there are some limitations in these methods. We used molecular biology techniques and established a database of allergen genes for wheat and hazelnut; and designed primers by finding the specific sequences. In order to find a rapid; convenient and efficient method for the detection of allergen;we implemented a real time fluorescence PCR method for a rapid screening of the allergen gene. It is simple; low-cost; easy for operation and time saving. The detection limit was increased; and miss-dection rate was lowed. Through the applicability test and LOD experiments; we found the method is applicable for the identification of allergens; good repeatability and accuracy with the detecting limit of 1% .