A high performance liquid chromatography-quadrupole/electrostatic field Orbitrap high resolution mass spectrometry（HPLC-Q/Orbitrap HRMS） was developed for the determination of aflatoxins in feeds.The IMMUNOPREP- ONLINE AFLATOXIN（Part Code:P900） was used as an online solid phase extraction column,and DiamonsilPlus C18（150 mm×4.6 mm,5 μm） as an analytical column.The feed samples were dissolved with a certain amount of NaCl and acetonitrile-water（80∶20）.After ultrasonic extraction,the supernatant was injected into an online solid phase extraction column,then the target was transferred to the analysis column by valve switching technique and HPD confocal elution mode for separation.The external standard method was used for quantitation.The analysis was performed by MS under Full scanning mode in positive mode.Under the optimal conditions,the calibration curves were linear in the range of 0.5-50.0 μg/L for four aflatoxin,the limits of detection and quantitation were 0.2 μg/kg and 0.5 μg/kg,respectively.The average recoveries at three spiked levels（0.5,1.0,5.0 μg/kg） were in the range of 94.6%-114.3% with relative standard deviations（RSDs） not more than 8.3%.With the advantages of rapidness,high automation,high-throughput detection and low cost,the proposed method could be used in the rapid detection on aflatoxins in feed samples.