A sensitively electrochemical aptasensor was developed to detect zearalenone, utilizing DNA assembly based on hybridization chain reaction to amplify the signal current and exonuclease III to reduce the background current. The linear range 5.0×10−5 ng/mL‐50 ng/mL, and the limit of detection is 0.013 pg/mL. The fabricated aptasensor showed the high specificity toward aflatoxin B1 (AFB1), fumonisin B1 (FB1) and ochratoxin A (OTA), good repeatability and reproducibility. In addition, the average recoveries of spiked corn and beer samples were in the range of 89 % to 102 %. The established method is of great significance in the field of food safety detection.