Zearalenone (ZEN) is mainly produced by Fusarium graminearum and widely exists in wheat， soybean and other grains and their derivatives. It has estrogen effect and a variety of toxicity， which can cause nervous system excitement. In this study， a fluorescence aptamer sensor based on Hairpin probe-mediated Isothermal Amplification (HIAmp) was established to detect ZEN in food. Firstly， a new hairpin probe was designed according to the ZEN aptamer sequence. Secondly， the hairpin structure was opened to initiate the amplification reaction by using the specific binding property of ZEN to the aptamer. Finally， a quantitative detection method of ZEN was established by combining with fluorescence technology， and the method was evaluated. The results showed that this method can complete the detection in about 1 h under the optimal reaction conditions， and the detection limit can reach 0.2 pg/mL. The linear equation constructed by -lgCZEN and Ct value was Ct = -1.195 lgCZEN + 14.082 (R2 = 0.9975)， and the linear relationship was good. The results of specific analysis showed that only two groups of samples containing ZEN produced signals， and the other five groups of samples without ZEN did not produce signals. The recoveries obtained by this method were 93.4%-99.6%， higher than those obtained by liquid chromatography (92.5%-99.0%) and ELISA kit(93.1%-98.4%). In summary， the fluorescent aptamer sensor based on hairpin probe mediated isothermal amplification constructed in this study has the advantages of strong specificity， short time consuming， simple operation， high sensitivity and high accuracy， and its detection limit is much lower than those of national standard liquid chromatography (5 μg/kg) and ELISA kit method (0.5 ng/mL). It provides a new strategy for the quantitative detection of ZEN in cereal foods and has a good application prospect in the field of food safety detection.