Abstract:A rapid detection method was developed. The samples were addition with 2，4 -dinitrophenylhydrazine under acidic conditions， detected by HPLC UV detector. The mobile phase was acetonitrile ∶ water （6 ∶ 4， mL/mL）， at a pump flow rate of 1.0 mL/min， detection wavelength of 355 nm. Under the optimal conditions， the linear range of formaldehyde was 0.05 μg/kg-5.0 μg/kg with correlation coefficient higher than 0.999 9， the limit of quantification was 0.5 mg/kg， the mean recoveries were 80.2 %-107.7 %. This method was simple， rapid and suitable for most food matrices such as flour， vermicelli， shrimp， bamboo shoots， yuba， fish （Carp， Squid etc）， blood tofu etc.